Question

I need help on questions 48 49 and 50 and u need to find the surface area of the 3 polyhedras please and thank you!

Answer 1

48. The surface area of a cylinder is given by

... A = 2πr² + 2πrh = 2πr(r+h)

For r = 13 mi and h = 7 mi, this becomes

... A = 2π(13 mi)(13 mi + 7 mi) = 520π mi²

The surface area of the cylinder is 520π mi² ≈ 1634 mi².

49. The surface area of a rectangular prism is

... A = 2(LW + H(L+W))

For L = 20 m, W = 10 m, H = 7 m, this becomes

... A = 2((20 m)(10 m) + (7 m)(20 m + 10 m)) = 2(200 m² + 210 m²) = 820 m²

The surface area of the prism is 820 m².

50. The formula is the same as for problem 48.

For r = 10 m and h = 13 m, this becomes

... A = 2π(10 m)(10 m + 13 m) = 460π m² ≈ 1445 m²

The surface area of the cylinder is 460π m² ≈ 1445 m².

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