You need to find the marginal rate of the given function, hence, you need to differentiate the function with respect to the argument x, such that:

`f'(x) = (x^5)' => f'(x) = 5x^4`

You need to evaluate the derivative of the function at `x = 2` , such that:

`f'(2) = 5*2^4 => f'(2) = 5*16 = 80`

**Hence, checking of the rate of change of the given function at `x = 2` is `f'(2) = 80` yields that the statement is valid.**