Interpreting Parameters in Linear/Exponential Models Practice Test

A taxi company charges a flat pickup fee plus a per-mile charge. The total fare is modeled by $F = 2.75m + 4.50$, where $m$ is the number of miles traveled. What does the parameter $4.50$ represent in this context?

A savings account balance is modeled by $B(t)=1200(1.03)^t$, where $B$ is the balance in dollars and $t$ is time in years. In the function $B(t)=1200(1.03)^t$, interpret the parameter 1200 in context.