How much will the surface area increase when a cylinder with a bottom diameter of 2 decimeters and a height of 5 decimeters is sawed into two cylinders of exactly the same size?

How much will the surface area increase when a cylinder with a bottom diameter of 2 decimeters and a height of 5 decimeters is sawed into two cylinders of exactly the same size?

Bottom radius 10cm, area = 3.14 * 10 * 10 = 314
Two floor areas have been increased, i.e. 628 square centimeters

A cylindrical timber is 1.2 meters long. After sawing it into two parts along the bottom diameter, the surface area increases by 500 square meters. What is the volume of this timber?

The increased surface area is based on the bottom diameter as long, height as wide and two rectangles
1. Bottom diameter = 500 △ 2 △ 1.2 = 125 radius = 125 △ 2 = 62.5m
2. The volume of cylinder is 3.14 × 62.5 ^ 2 × 1.2 = 14718.75 cubic meters
There's something wrong with the unit of the title! There's such a large amount of wood. If you give it the wrong way, you can unify the unit by yourself. The method is the same

Saw a 20 cm diameter, 2 m long cylindrical wood into the same three sections, the surface area increased______ Cubic centimeter

The answer is: the surface area is increased by 1254.4 × 10 2