Interpreting Function Notation, Graphs, and Context

The owner of a new racing team is trying to estimate the cost for each series before he commits to one. He has come up with the following variables: $$\begin{align} \text{Cost}&=\text{Total cost of season}\\ A&=\text{Average cost of travelling}\\ t&=\text{Number of times travelling}\\ B&=\text{Average cost of parts}\\ p&=\text{Number of parts}\\ C&=\text{Average cost of repairs}\\ r&=\text{Number of repairs needed}\\ E&=\text{Average payout from wins}\\ w&=\text{Number of wins} \end{align}$$

The owner's basic model for the season is as follows: $$\text{Cost}= At+Bp+Cr-Ex$$

How could this be written in function notation?