Answer:
1200 ft²
Step-by-step explanation:
We assume that we want the total surface area, which includes the curving sides and the flat ends.
1. Curving sides: We are actually finding the area of a flat piece of material whose length is C = 2πr and whose width is the height of the cylinder, h. Then this side area is A = 2πrh. Here, that area is
A = 2π(15 ft)(25 ft) = 750π ft²
2. Ends: The end area is A = πr², and there are two ends.
The total area of the ends is A = 2πr², which here is A = 2π(15 ft)², or
A = 450π ft².
Thus, the total exact surface area of this cylinder is
A = 450π ft² + 750π ft² = 1200 ft²
