A Study Indicates That X Months from Now the Population $( 3 + 3 x ) x ^ { - 1 / 2 }$

Multiple Choice

A study indicates that x months from now the population of a certain city will be increasing at the rate of $( 3 + 3 x ) x ^ { - 1 / 2 }$ people per month.By how much will the population increase over the next 9 months?

A) 54 people
B) 62 people
C) 72 people
D) 82 people