The diameter of the small cylinder is 6cm, the height is 12cm, the diameter of the large cylinder is 12cm, and its volume is twice the volume of the small cylinder?

The diameter of the small cylinder is 6cm, the height is 12cm, the diameter of the large cylinder is 12cm, and its volume is twice the volume of the small cylinder?

The volume of small cylinder is 3.14 × (6 / 2) & # 178; × 12 = 28.26 × 12 = 339.12 cubic centimeter, the volume of large cylinder is 339.12 × 2 = 678.24 cubic centimeter, the bottom area of large cylinder is 3.14 × (12 / 2) & # 178; = 3.14 × 36 = 113.04 square centimeter, the height of large cylinder is volume ／ bottom area

3、 Calculate the surface area and volume of the following figures: cylinder, 6 cm diameter cuboid, 15 cm length and 10 cm width
The other cylinder is 14cm in diameter and 5cm in height

The surface area is 90 π, 130018 π, and the volume is 108 π, 3000245 π, respectively
The last value you added later is a cylinder with a diameter of 14cm and a height of 5cm
Cylinder side is rectangular, the bottom is circular (with two bottom), the surface area is very easy to calculate; cuboid is not much to say
Volume is bottom (area of circle) x height, cuboid is length x width x height