I cannot see your picture, but if the plane cutting the cylinder is indeed perpendicular to the cylinder's base, then the cross section must be square or rectangular. Going by the shape of most cylinders, I would guess that it is rectangular.
Take into account, that in general, a cosine function of amplitude A, period T and vertical translation b, can be written as follow:

In the given case, you have:
A = 4
T = 3π/4
b = -3
By replacing you obtain:

Hence, the answer is:
f(x) = 4cos(8/3 x) - 3
Answer:
C. (-4x^2)+2xy^2+[10x^2y+(-4x^2y)
Step-by-step explanation:
A. [9-4x2) + (-4x2y) + 10x2y] + 2xy2 : in this polynomial the first term is not a like term, then this is incorrect.
B. 10x2y + 2xy2 + [(-4x2) + (-4x2y)] : in this polynomial, the terms that are grouped, are not like terms, then is incorrect.
C. (-4x2) + 2xy2 + [10x2y + (-4x2y)] ; This polynomial is the right answer because the like terms are grouped.
D. [10x2y + 2xy2 + (-4x2y)] + (-4x2): This polynomial is incorrect because one of the terms that are grouped is not a like term.
1. You have that:
- The trapezoids are similar.
- The larger base of the smaller trapezoid is 18 m and its area is 310 m².
- The larger base of the larger trapezoid is 32 m.
2. Then:
Sides=18/32
Sides=9/16
Area=(9/16)²
Area=81/256
3. Now, you can find the area of the larger trapezoid, as below:
81/256=310/x
81x=(310)(256)
x=79360/81
x=980 m²
Therefore, the answer is: The area of the larger trapezoid is 980 m².