rise

A: B: C =2: 4: 7, and the average of the three numbers A: B: C is 260, and the maximum number is ().

The radius of the bottom of the cylinder is 2 decimeters, and its side is square. The height of this cylinder is () 2.

The radius of a circle is out of proportion to its area. ()

The volume of a cylinder is three times that of a cone ()

Answer: 205

28

420

12.56

correct

wrong