Area = length * width +2* (length+width) * height =12 * 5+2 * (12+5) * 2 = 60+68 =128 square decimeter.

Volume = length * width * height = 12*5*2= 120 cubic decimeter.

2

Coverage = length * width = 50 * 30 = 1500m2.

Volume = length * width * depth = 50 * 30 * 1.5 = 22500m3.

Water injection per minute = volume/time = 22500/(12 * 60) = 31.25m3.

three

Stone volume = water volume = length * width * height =80*60*2=9600 cubic centimeters.

four

If the side length of the cube is x

The surface area of a cuboid is 14*x*x=56.

X = 2 cm

The surface area is 6*2*2=24 square centimeters.

The volume of each small cube =2*2*2=8 cubic centimeters.

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Supplement:

If it must be formulated, after three small cubes are put together into a cuboid, a * * is 3*6-2*2= 14 faces.

The surface area of a cuboid is 56 square centimeters, and 56/ 14=4 square centimeters, that is, one side of a small cube is 4 square centimeters.

The side length is 2cm, and the surface area is 6 * 2 * 2 = 24cm2.

The volume is 2*2*2=8 cubic centimeters.