1. 

What is the volume of a cube?

I.  The area of each face of the cube is 64 square metres.

II. The length of one side of the cube is 8 metres.

A. I alone sufficient while II alone not sufficient to answer
B. II alone sufficient while I alone not sufficient to answer
C. Either I or II alone sufficient to answer
D. Both I and II are not sufficient to answer
E. Both I and II are necessary to answer

Answer: Option C

Explanation:

Let each edge be a metres. Then,

I. a2 = 64       a = 8 m       Volume = (8 x 8 x 8) m3 = 512 m3.

Thus, I alone gives the answer.

II. a = 8 m       Volume = (8 x 8 x 8) m3 = 512 m3.

Thus, II alone gives the answer.

Correct answer is (C).