I assume this is exercise #1 on the worksheet for f(x) notation. You need to be specific when asking questions.

The instruction should read

'Of course you know, or at least suspect, that your function models won't always be quadratic. Obtain the indicated expressions for the following functions, none of which are quadratic:'

For example if the function was f(t) = t^5 and you were asked to find f(2), f(3z) and f(a+b) your answers would be 2^5, (3z)^5 and (a + b)^5.