A cylinder with a bottom circumference of 25. 12cm and a height of 10cm is cut into several equal parts to form an approximate cuboid. The bottom area of this cuboid is ()

A cylinder with a bottom circumference of 25. 12cm and a height of 10cm is cut into several equal parts to form an approximate cuboid. The base area of this cuboid is (50.24) cm2, the surface area is (43 1.68) cm2, and the volume is (502.4) cm3.

(1) The bottom area of a cuboid is equal to the bottom area of a cylinder:

(25. 12cm÷3. 14÷2)？ ×3. 14= 16cm？ × 3.14 = 50.24cm2.

(2) The width of a cuboid is the radius of a cylinder. The length of a cuboid is half the circumference of a cylinder;

Length: 25.12 ÷ 2 =12.56cm.

Width: 25.12cm÷ 3.14÷ 2 = 4cm.

Height:10cm

Surface area: (4×12.56+4×10+12.56×10) × 2 = 431.68cm2.

(3) The volume of a cuboid is equal to the volume of a cylinder:

50.24cm？ × 10cm = 502.4cm3。