What is the surface area of a cylinder with a height of 10 cm and a bottom radius of 5 decimeters?

What is the surface area of a cylinder with a height of 10 cm and a bottom radius of 5 decimeters?

3.14 × 5 × 5 × 2 + (5 + 5) × 3.14 × 1 = 188.4 (square decimeter)
10 cm = 1 decimeter

The bottom radius of a cylinder is 3 decimeters. Find its side area and surface area

Hello, 714824ab
Side area:
3.14 × 2 × 3 × 10 = 188.4 (square decimeter)
Surface area:
3.14 × 3 ^ 2 × 2 + 188.4 = 244.92 (square decimeter)

A cylinder with a radius of 1 decimeter at the bottom and a height of 20 cm has a volume of 1______ And the surface area is______ ．

20 cm = 2 decimeter, bottom area: 3.14 × 12 = 3.14 (square decimeter), side area: 2 × 3.14 × 1 × 2 = 12.56 (square decimeter), surface area: 3.14 × 2 + 12.56 = 18.84 (square decimeter), volume: 3.14 × 2 = 6.28 (cubic decimeter)