Suppose That $z = x ^ { 3 } y ^ { 2 }$

Essay

Suppose that $z = x ^ { 3 } y ^ { 2 }$ , where both $x$ and $y$ are changing with time. At a certain instant when $x = 1$ and $y = 2$ , $x$ is decreasing at the rate of 2 units/s and $y$ is increasing at the rate of 3 units/s. How fast is $Z$ changing at this instant? Is $Z$ increasing or decreasing?