In the formula A = (2r)^3, if r is halved, then A is multiplied by ?
Choose the correct choice from the following:
A) 64
B) 1 / 8
C) 1
D) 8
E) 1 / 64

Rationale: say r = 2 = > a 1 = 64 when r = 1 ; v 2 = 8 v 2 = 1 / 8 * v 1 . answer : b
Answer: B