How do I solve this rate law problem

Question

A reaction has the experimental rate law of rate=k [A]^2

 

A. What happens to the rate if the concentration of A is tripled?

 

B. What happens to the rate if the concentration if A is reduced to 1/3 the initial concentration?

Answer 1

Since k is a constant, just look at rate = [A]²

If [A] = 1 the rate is 1² = 1

If you triple the [A] to [A] = 3, the rate is 3² = 9.  This is the answer to part A

(B).  Here instead of [A] = 1 and rate = 1, [A] = 0.333 and rate = 0.333² = 0.111 so rate is reduced to 11% of original rate