The surface area of a cylinder is () square meters if its bottom area is 7 square meters

The surface area of a cylinder is () square meters if its bottom area is 7 square meters

If the radius is r m, then
πr²=7
The side view is a square
The height is 2 π r M
Surface area: 7 × 2 + (2 π R) &# 178; = 14 + 4 π & # 178; R & # 178; = 14 + 4 π * π R & # 178; = 14 + 28 π (M2)

The expanded side area of a cylinder is a 15.7cm square. What is the surface area of the cylinder?

Bottom radius: 15.7 △ 3.14 △ 2 = 2.5 (CM), surface area: 15.7 × 15.7 + 3.14 × 2.52 × 2, = 246.49 + 39.25, = 285.74 (cm 2). Answer: the surface area of this cylinder is 285.74 cm 2

If the height of a cylinder is reduced by 2cm, the surface area will be reduced by 37.68 square cm. What is the circumference of the bottom surface of the cylinder?

From the meaning of the title:
Reduced floor area
=Reduced side area
=Bottom perimeter × 2
So:
Bottom circumference = 37.68 △ 2 = 18.84 cm

If the height of a cylinder is increased by 2cm, the surface area will increase by 12.56 square cm, and the side of the cylinder will be expanded into a square. Calculate the volume of the original cylinder

Bottom perimeter = 12.56 / 2 = 6.28
Bottom radius = 6.28/3.14/2 = 1
h=6.28-2=4.28
Bottom area = 1 * 1 * 3.14 = 3.14
Volume = 4.28 * 3.14
(the one upstairs asked about the original volume)