Answer:
the amount of 50% silver alloy is 6 kilograms and the amount of 25% silver alloy is (10-6)= 4 kilograms.
Step-by-step explanation:
Suppose, the weight of the alloy with 50% silver content is x kilograms.
As, the weight of the mixed alloy should be 10 kilograms, so the weight of the alloy with 25% silver content will be: kilograms
The percentage of silver content in the mixed alloy is 40%. So the equation will be calculated as
[tex]0.5x+0.25(10-x)=0.4\times10\\0.5x+2.5-0.25x=4\\0.25x=1.5\\\Rightarrow x=\frac{1.5}{0.25} = 6[/tex]
So, the amount of 50% silver alloy is 6 kilograms and the amount of 25% silver alloy is (10-6)= 4 kilograms.
Find the SURFACE AREA of this composite solid.
FINDING THE SURFACE AREA OF A COMPOSITE SOLID
About "Finding the surface area of a composite solid"
Finding the surface area of a composite solid :
A composite solid is made up of two or more solid figures.
To find the surface area of a composite solid, find the surface area of each figure. Subtract any area not on the surface.
Finding the surface area of a composite solid - Examples
Example 1 :
Daniel built the birdhouse shown below. What was the surface area of the birdhouse before the hole was drilled ?
Solution :
Step 1 :
Identify the important information.
• The top is a triangular prism with h = 24 cm. The base is a triangle with height 8 cm and base 30 cm.
• The bottom is a rectangular prism with h = 18 cm. The base is a 30 cm by 24 cm rectangle.
• One face of each prism is not on the surface of the figure.
Step 2 :
Find the surface area of each prism.
Add the areas. Subtract the areas of the parts not on the surface.
Step 3 :
Find the area of the triangular prism.
Perimeter = 17 + 17 + 30 = 64 cm
Base area = (1/2)(30)(8) = 120 sq.cm
Surface area = Ph + 2B
Surface area = 64(24) + 2(120)
Surface area = 1,776 sq.cm
Step 4 :
Find the area of the rectangular prism.
Perimeter = 2(30) + 2(24) = 108 cm
Base area = 30(24) = 720 sq.cm
Surface area = Ph + 2B
Surface area = 108(18) + 2(720)
Surface area = 3,384 sq.cm
Step 5 :
Add. Then subtract twice the areas of the parts not on the surface.
Surface area = 1,776 + 3,384 - 2(720) = 3,720 sq.cm
The surface area before the hole was drilled was 3,720 sq.cm.
The surface area before the hole was drilled was; 3,720 sq.cm.
What is composite solid?A composite solid is made up of two or more solid figures.
To determine the surface area of a composite solid, find the surface area of each figure. Subtract any area not on the surface.
Given that the top is a triangular prism with h = 24 cm. The base is a triangle with height 8 cm and base 30 cm.
The bottom is a rectangular prism with h = 18 cm.
The base is a 30 cm x 24 cm rectangle.
One face of each prism is not on the surface of the figure.
Then the surface area of each prism.
Add the areas. Subtract the areas of the parts not on the surface.
The area of the triangular prism.
Perimeter = 17 + 17 + 30 = 64 cm
Base area = (1/2)(30)(8) = 120 sq.cm
Surface area = Ph + 2B
Surface area = 64(24) + 2(120)
Surface area = 1,776 sq.cm
Now the area of the rectangular prism.
Perimeter = 2(30) + 2(24) = 108 cm
Base area = 30(24) = 720 sq.cm
Surface area = Ph + 2B
Surface area = 108(18) + 2(720)
Surface area = 3,384 sq.cm
Now,
Surface area = 1,776 + 3,384 - 2(720) = 3,720 sq.cm
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What is the equation of the following line? Be sure to scroll down first to see all answer options.(0,0)(4,-2)
Answer:
i hope this helps you
The Equation of the line is 2y = -x.
What is the equation of a line passing through two given points in 2 dimensional plane?Suppose the given points are (x_1, y_1) and (x_2, y_2), then the equation of the straight line joining both two points is given by
[tex](y - y_1) = \dfrac{y_2 - y_1}{x_2 - x_1} (x -x_1)[/tex]
Given Points of the line are (0,0) and (4,-2).
Since we are given two points.
[tex](y - y_1) = \dfrac{y_2 - y_1}{x_2 - x_1} (x -x_1)\\\\\\(y - (-2)) = \dfrac{-2- 0}{4 - 0} (x -4)\\\\\\(y - (-2)) = \dfrac{-1}{2} (x -4)\\\\2(y + 2) =-1(x -4)\\\\2y + 4 = -x + 4\\\\2y = -x\\\\[/tex]
Therefore, Equation of the line is 2y = -x.
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liam is a tyre fitter it takes him 56 minutes to fit 4 tyres to a van
Answer:
Step-by-step explanation:
I am not really sure because u did not finish the question but is u are asking how much time it takes to fit one tyre:
answer is time/tyres
56min./4
14 min. Per type
Find the value of y when equals zero. -7x+3y=30
Answer:
x = -30/7
Step-by-step explanation:
-7x+3y=30
Let y=0
-7x +0 = 30
Divide by -7
-7x /-7 = 30/-7
x = -30/7
Answer:
[tex]-\frac{30}{7}[/tex]
Step-by-step explanation:
y equals zero => y = 0
-7x+3y=30
-7x +3.0 = 30
-7x + 0 = 30
-7x = 30
-7x/-7 = 30/-7
x = -30/7
Hope this helps ^-^
Please answer this correctly
Answer:
4 pizza recipes
Step-by-step explanation:
It shows 4 Xs after the [tex]\frac{3}{4}[/tex] mark. So there are 4 recipes that use MORE than [tex]\frac{3}{4}[/tex] cups of cheese.
Answer:
4 cups of cheese
Step-by-step explanation:
More than 3/4 are (3+1) = 4 cups of cheese
Mark Wishing the Brainliest because he deserves it :)
Los Angeles workers have an average commute of 33 minutes. Suppose the LA commute time is normally distributed with a standard deviation of 15 minutes. Let X represent the commute time for a randomly selected LA worker. Round all answers to 4 decimal places where possible.
a. What is the distribution of X? X N
b. Find the probability that a randomly selected LA worker has a commute that is longer than 38 minutes
c. Find the 80th percentile for the commute time of LA workers. _______ minutes
Answer:
a) N(33,15).
b) 37.33% probability that a randomly selected LA worker has a commute that is longer than 38 minutes
c) 45.6 minutes.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
[tex]\mu = 33, \sigma = 15[/tex]
a. What is the distribution of X?
Normal with mean 33 and standard deviaton 15. So
N(33,15).
b. Find the probability that a randomly selected LA worker has a commute that is longer than 38 minutes
This is 1 subtracted by the pvalue of Z when X = 38. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{38 - 33}{15}[/tex]
[tex]Z = 0.333[/tex]
[tex]Z = 0.333[/tex] has a pvalue of 0.6267.
1 - 0.6267 = 0.3733
37.33% probability that a randomly selected LA worker has a commute that is longer than 38 minutes
c. Find the 80th percentile for the commute time of LA workers.
This is X when Z has a pvalue of 0.8. So it is X when Z = 0.84.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]0.84 = \frac{X - 33}{15}[/tex]
[tex]X - 33 = 0.84*15[/tex]
[tex]X = 45.6[/tex]
45.6 minutes.
You are situated 300 feet from the base of Tower Glitz Plaza watching an external elevator descend down the side of the building. At a certain instant the elevator is 500 feet away from you, and its distance from you is decreasing at a rate of 16 ft/sec. How fast is the elevator descending at that instant?
Answer:
18.66 ft/s
Step-by-step explanation:
The distance between you and the elevator is given by:
[tex]h=\sqrt{x^2+y^2}[/tex]
The rate of change for the distance between you and the elevator is given by:
[tex]\frac{dh}{dt}=\frac{dh}{dy}*\frac{dy}{dt}[/tex]
[tex]-16=\frac{dh}{dy}*\frac{dy}{dt}[/tex]
[tex]\frac{dh}{dy}=\frac{d}{dy} (\sqrt{x^2+y^2})\\[/tex]
Applying the chain rule:
[tex]u=x^2+y^2\\\frac{dh}{dy}=\frac{d\sqrt u}{du} *\frac{du}{dy}\\\frac{dh}{dy}=\frac{1}{2\sqrt u} *2y\\\frac{dh}{dy}=\frac{y}{\sqrt {(x^2+y^2)}}[/tex]
Therefore, at x=300 and y = 500, dy/dt is:
[tex]-16=\frac{y}{\sqrt {(x^2+y^2)}}*\frac{dy}{dt}\\-16=\frac{500}{\sqrt {(300^2+500^2)}}*\frac{dy}{dt}\\\frac{dy}{dt}=-18.66\ ft/s[/tex]
The elevator is descending at 18.66 ft/s.
Which equation does not represent a linear function of x?
a. y = -3 over 4 x
b. y = x over 2
c. y = - 3 + 2x
d. y = 3x2 - 2
Thw sum of 12x^2+9x^2
Answer:
21 x^2
Step-by-step explanation:
12x^2+9x^2
Combine like terms
x^2(12+9)
x^2(21)
21 x^2
One number is 3 more than 2 times the other, and their sum is 27. Find the numbers.
If x represents the smaller number, then the larger number is
3x + 2
2x + 3
21x + 3)
Answer:
Option 2 is correct
Step-by-step explanation:
One number is 2 times another number plus 3. Their sum is 21.
"One number is 2 times another number plus 3" translated to
x = smaller number = another number
It is also given that: Their sum is 21.
Combine like terms:
3x+3 = 21
Answer:
I do questions like these everyday so I have too much experience. Let me explain step by step for you.
Brainliest?
First lets set 2 variables x and y
Lets make 2 equations.
x=3+2*y
Thats because it says 'x' is 3 more (+) than 2 times(*) 'y'
Now lets set second, we know both of them add up to 27.
x+y = 27
Since we know what x is equal to (look above equation)
We can replace it.
x is replaced with 3+2*y
3+2y+y = 27
3+4y = 27
Simplify 27-3 = 24
24/4 = 6
Now lets plug in for x
3+2*6 = 15
15 - x
6 - y
:))
A company studied the number of lost-time accidents occurring at its Brownsville, Texas, plant. Historical records show that 5% of the employees suffered lost-time accidents last year. Management believes that a special safety program will reduce such accidents to 4% during the current year. In addition, it estimates that 15% of employees who had lost-time accidents last year will experience a lost-time accident during the current year. a. What percentage of the employee will experience a lost-time accident in both years (to 1 decimal)?
Answer:
The percentage of the employee will experience a lost-time accident in both years is 0.0%
Step-by-step explanation:
Let A denote events that employees suffered lost-time accidents during the last year
Let B denote events that employees suffered lost-time accidents during the current year
P(A) = 5% = 0.05
P(B) = 4% = 0.04
P(B | A) = 15% = 0.15
(a) P (A ∩ B) = P(B | A) × P(A)
= 0.15 × 0.05
= 0.0075
= 0.0 (1 decimal place)
The probability that an employee will experience a lost- time accident in both years is 0.0
Steve drove for 812 hours at 72 miles per hour. How much distance did he travel
Answer:
[tex]58,464 \: \: miles[/tex]
Step-by-step explanation:
[tex]speed = \frac{distantce}{time} \\ [/tex]
[tex]distance = speed \times time \\ x = 72 \times 812 \\ x = 58,464 \: \: miles[/tex]
hope this helps
brainliest appreciated
good luck! have a nice day!
Which statement about the two-way frequency table is true?
Answer:
Which statements?
Step-by-step explanation:
Can you write the statements please?
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
D. It would be less steep.
Step-by-step explanation:
→When the absolute value of the number in front of x is greater than 1, the function on the graph narrows. When the absolute value of the number in front of x is less than 1, the function on the graph widens.
In this case, the number is less than 1, making it grow wider. And as a result of it growing wider, it also becomes less steep.
Rebecca Pearson is a widow and needs to take care of the expenses in her household. Her budget is below.
Find her net monthly cash flow. (Assume 1 month = 4 weeks)
Income Expenses
Salary: $2300/month
Rent: $1090/month
Groceries: $200/week
Utilities: $125/month
Car Insurance: $525 semiannually
Gasoline: $25/week
Miscellaneous: $200/month
Phone: $50/month
Hey there!
First, let's take all of the expenses and change the ones that aren't monthly into monthly.
Groceries: $800/month
Car insurance: $87.5/month
Gasoline: $100/month
Now, let's add together all of our expenses
1090+800+125+87.5+100+200+50=2452.5
Now, we subtract that from her salary.
2300-2452.5=-152.5
Therefore, Rebecca's net monthly cash flow is -$152.5. She should spend a bit less on groceries, not do so much miscellaneous, find a place that charges less rent, drive less, etc. so she isn't spending more than she earns.
I hope that this helps! Have a wonderful day!
Which of the given shapes has a larger area?
Answer:
Rectangle
Step-by-step explanation:
Count the units. For the triangle, A=0.5bh. 0.5(4)(6)=A. A=12
Now, for the rectangle, A=bh. A=(3)(5). A=15. The rectangle is larger
Simplify: 5y + 2p – 4y – 6P
Answer:
[tex]y-4p[/tex]
Step-by-step explanation:
Add/subtract like terms.
[tex]5y+2p-4y-6p\\5y-4y+2p-6p\\y-4p[/tex]
In △DEF, d = 25 in., e = 28 in., and f = 20 in. Find m∠F. Round your answer to the nearest tenth.
Answer:
∠F ≈ 43.9°
Step-by-step explanation:
The Law of Cosines is used to find an angle when all triangle sides are known.
f² = d² +e² -2de·cos(F)
cos(F) = (d² +e² -f²)/(2de) = (25² +28² -20²)/(2·25·28) = 1009/1400
F = arccos(1009/1400)
F ≈ 43.9°
Solve the following system of equations using the elimination method. 5x – 5y = 10 6x – 4y = 4
Answer:
11×-9y=14
Step-by-step explanation:
123hsvwjwjbe
Answer:
(-2,-4)
Step-by-step explanation:
add the equations in order to solve the first variable. put the value into the other equations in order to solve the other variables.
In order to get toys from under the couch, Mom lifted up the couch to an angle of 31 degrees. The kids still could not reach the toys. Then, she lifted it up another 15 degrees, and the kids pulled out a bouncy ball, a foam dart, three rubber bands, and a Lego. What was the measure of the total angle Mom lifted the couch?
Answer:
46 degrees
Step-by-step explanation:
Add 31 + 15 together to find the total angle
31 + 15 = 46
= 46 degrees
Answer:
That is 46°.
Step-by-step explanation:
31 + 15 = 46
So, 46°.
A research scientist wants to know how many times per hour a certain strand of bacteria reproduces. The mean is found to be 7.8 reproductions and the population standard deviation is known to be 2.2. If a sample of 697 was used for the study, construct the 85% confidence interval for the true mean number of reproductions per hour for the bacteria. Round your answers to one decimal place.
Answer:
The 85% confidence interval is ( 7.7 , 8.0 )
Step-by-step explanation:
In order to find the 85% confidence interval you use the following formula:
[tex]\overline{x}\pm Z_{\alpha/2}\frac{\sigma}{\sqrt{n}}[/tex] (1)
where
[tex]\overline{x}[/tex]: mean of number of bacteria reproduces per hour = 7.8
σ: standard deviation = 2.2
n: sample size = 967
α: 1 - 0.85 = 0.15
Zα/2: Z factor of the density distribution = 1.44
You replace the values of all parameters in the equation (1):
[tex]7.8\pm (1.44)\frac{2.2}{\sqrt{697}}\\\\7.8\pm0.119\\\\[/tex]
Then, the confidence interval is:
[tex](7.8-0.119,7.8+0.119)\\\\(7.7,8.0)[/tex]
help asap, will get branliest !!
Answer:
D
Step-by-step explanation:
Lines EF and GH are already parallel. Translating them 2 units to the side without changing how far apart they are vertically means they won't intersect and will remain the same distance apart.
Answer:
D
Step-by-step explanation:
They are parallel lines
A large software company gives job applicants a test of programming ability and the mean for that test has been 160 in the past. Twenty-five job applicants are randomly selected from a large university and they produce a mean score of 183 with a standard deviation of 12. Use a 0.05 level of significance to test whether the mean score for students from this university is greater than 160. use the P-value method of testing hypotheses.
Answer:
[tex]t=\frac{183-160}{\frac{12}{\sqrt{25}}}=9.58[/tex]
The degrees of freedom are given by:
[tex]df=n-1=25-1=24[/tex]
And the p value would be:
[tex]p_v =P(t_{(24)}>9.58)\approx 0[/tex]
Since the p value is very low at any significance level we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly higher than 160
Step-by-step explanation:
Information provided
[tex]\bar X=183[/tex] represent the sample mean
[tex]s=12[/tex] represent the sample standard deviation
[tex]n=25[/tex] sample size
[tex]\mu_o =160[/tex] represent the value to test
[tex]\alpha=0.05[/tex] represent the significance level
t would represent the statistic
[tex]p_v[/tex] represent the p value
Hypothesis to test
We want to verify if the true mean is greater than 160, the system of hypothesis would be:
Null hypothesis:[tex]\mu \leq 160[/tex]
Alternative hypothesis:[tex]\mu > 160[/tex]
The statistic is given by:
[tex]t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}[/tex] (1)
Replacing the info we got:
[tex]t=\frac{183-160}{\frac{12}{\sqrt{25}}}=9.58[/tex]
The degrees of freedom are given by:
[tex]df=n-1=25-1=24[/tex]
And the p value would be:
[tex]p_v =P(t_{(24)}>9.58)\approx 0[/tex]
Since the p value is very low at any significance level we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly higher than 160
Suppose you
earn $10.30 per hour and work 24 eight-hour
days in a month. How much do you earn in that month?
Answer:1977.60
Step-by-step explanation:
24x8= 192
192x 10.30= 1977.60
y - 15=x Solve for Y
Answer:
y = x+15
Step-by-step explanation:
y - 15=x
Add 15 to each side
y - 15+15=x+15
y = x+15
Answer:
[tex]y=x+15[/tex]
Step-by-step explanation:
[tex]y - 15=x[/tex]
Add [tex]15[/tex] on both sides of the equation.
[tex]y - 15+15=x+15[/tex]
The [tex]y[/tex] should be isolated on one side of the equation.
[tex]y=x+15[/tex]
Two samples are randomly selected from each population. The sample statistics are given below.
n1 = 150 n2 = 275
x1 = 72.86 -x2 = 67.34
s1 = 15.98 s2 = 35.67
The value of the standardized test statistic to test the claim that μ1 > μ2 is _________.
-2.19
2.19
3.15
-3.15
Answer:
Null hypothesis: [tex]\mu_1 \leq \mu_2[/tex]
Alternative hypothesis: [tex]\mu_1 > \mu_2[/tex]
The statistic is given by:
[tex]t= \frac{\bar X_1 -\bar X_2}{\sqrt{\frac{s^2_1}{n_1} +\frac{s^2_2}{n_2}}}[/tex]
And replacing we got:
[tex] t=\frac{72.86-67.34}{\sqrt{\frac{15.98^2}{150} +\frac{35.67^2}{275}}}=2.194[/tex]
And the best option would be:
2.19
Step-by-step explanation:
We have the following info given:
n1 = 150 n2 = 275
[tex]\bar x_1 = 72.86, \bar x_2 = 67.34[/tex]
s1 = 15.98 s2 = 35.67
We want to test the following hypothesis:
Null hypothesis: [tex]\mu_1 \leq \mu_2[/tex]
Alternative hypothesis: [tex]\mu_1 > \mu_2[/tex]
The statistic is given by:
[tex]t= \frac{\bar X_1 -\bar X_2}{\sqrt{\frac{s^2_1}{n_1} +\frac{s^2_2}{n_2}}}[/tex]
And replacing we got:
[tex] t=\frac{72.86-67.34}{\sqrt{\frac{15.98^2}{150} +\frac{35.67^2}{275}}}=2.194[/tex]
And the best option would be:
2.19
Use Greens Theorem to evaluate integral x^2ydx - xy^2dy, where C is 0 ≤ y ≤ √9-x^2 with counterclockwise orientation
Answer:
Step-by-step explanation:
a circle will satisfy the conditions of Green's Theorem since it is closed and simple.
Let's identify P and Q from the integral
[tex]P=x^2 y[/tex], and [tex]Q= xy^2[/tex]
Now, using Green's theorem on the line integral gives,
[tex]\oint\limits_C {x^2ydx-xy^2dy } =\iint\limits_D {y^2-x^2} \, dA\\\\[/tex]
Jan's All You Can Eat Restaurant charges $9.10 per customer to eat at the restaurant. Restaurant management finds that its expense per customer, based on how much the customer eats and the expense of labor, has a distribution that is skewed to the right with a mean of $8.10 and a standard deviation of $4.
A. If the 100 customers on a day have the characteristics of the random sample from their customer base, find the mean and standard error of the sampling distribution of the restaurant's sample mean expense per customer.
B. Find the probability that the restaurant makes a profit that day, with the sample mean expense being
less than $8.95.
Answer:
Step-by-step explanation:
From the given question;
Given that:
Jan's All You Can Eat Restaurant charges $9.10 per customer to eat at the restaurant.
Distribution is skewed and and has a mean of $8.10 and a standard deviation of $4.
A. If the 100 customers on a day have the characteristics of the random sample from their customer base, find the mean and standard error of the sampling distribution of the restaurant's sample mean expense per customer.
the mean by using the central limit theorem is 8.10
the standard error of the sampling distribution = [tex]\dfrac{\sigma}{\sqrt{n}}[/tex]
the standard error of the sampling distribution = [tex]\dfrac{4}{\sqrt{100}}[/tex]
= 4/10
= 0.4
B.
P(X > $8.95) = P (Z > 8.95 - 8.10/0.4)
P(X > $8.95) = P (Z > 2.1)
P(X > $8.95) = 1 - P (Z < 2.1)
P(X > $8.95) = 1 - 0.9821
P(X > $8.95) = 0.0179
On a piece of paper, graph fx) = 2• (0.5)*. Then determine which answer choice matches the graph you drew.
Answer:
Graph A
Step-by-step explanation:
The common ratio is less than 1, so the graph will be decreasing. The initial value is 2, so the y-intercept will be 2. Graph A fits this criteria.
I hope this helps :))
The graph A is correct.
What is a graph?A diagram (such as a series of one or more points, lines, line segments, curves, or areas) that represents the variation of a variable in comparison with that of one or more other variables.
The equation is,
[tex]y=2(0.5)^{x}[/tex]
Plotting the graph, we get,
Option A
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Makeeya only has $25 to spend on a custom T-shirt. It costs $10 for a plain T-shirt, and there is a charge of $$1.50 for each square inch of design added to the T-shirt. Which solution represents the number of square inches of design,x , Makeeya can put on her T-shirt?
Answer:
10 square inches
Step-by-step explanation:
cost of a plain t-shirt = $10
cost of 1 square inch of design addition = $1.50
let there be x square inches of design
then cost of x square inches of design = x*cost of 1 square inch of design
= 1.50*x = 1.5x
Total cost for t-shirt with x square inches of design = cost of a plain t-shirt + cost of x square inches of design = 10 + 1.5 x
It is given that Makeeya has only $25, then total cost which can be afforded by him will be $25 only
Thus,
10 + 1.5 x = 25
=> 1.5x = 25-10 = 15
=> x = 15/1.5 = 10
Thus, Makeeya can put 10 square inches of design on her T-shirt.
