<h2><u>D:</u></h2><h2><em /></h2><h2><em>The awnser is </em><u><em>4</em></u><em>!! Hope this helps!! <3</em></h2>
The parametric equations for x and y describe a circle of radius 10 m, so the length of the base of the fence is the length of the circumference of a circle of radius 10 m. The formula for that circumference (C) is ...
... C = 2πr
... C = 2π·(10 m) = 20π m
The height as a function of angle (t) is found by substituting for x and y.
... h(t) = h(x(t), y(t)) = 4 + 0.01·((10cos(t))²-)10sin(t))²) = 4+cos(2t)
The average value of this over the range 0 ≤ t ≤ 2π is 4, since the cosine function has two full cycles in that range, and its average value over a cycle is zero.
Thus, the area of one side of the fence is that of a rectangle 20π m long and 4 m wide. That will be
... (20π m)·(4 m) = 80π m²
The amount of paint required to cover both sides of the fence is
... 2×(80π m²)×(1 L)/(10 m²) = 16π L ≈ 50.3 L
_____
You can work out the integral for area as a function of t. When you do, you will find it gives this same result.
Its basically just subtracting from one another
for example, 6-6 is 6
or -4-3= 7
29. A carpenter worked for 4 days to finish a repair job. She charged $825 for 15 hours plus $278 for materials. What is the carpenter's rate per hour?
Let’s start solving:
=> 825 dollars + 278 dollars = 1 103 dollars is the total payment a carpenter have received
=> 15 hours is the total hours he worked
=> 1 103 / 15 = 73.5 dollars per hour. This is already including the material or equipment fee.
