Evaluate the summation from n equals 1 to infinity of the quotient of 3 and 2 raised the quantity n minus 1 power

Question

Evaluate  

A	12
B	6
C	3
D	0

Answer 1

Hint: sum from 1 to infinity of ar^n-1 where a is a constant and absolute value of r < 1 = a/(1-r)