pls help , someone answered my previous question for this to take points and im kinda low and new here so please just help me.

Jabari is power washing houses for a summer job. for every job, he charges an initial fee plus $30 for each hour of work. his total fee for a 4 -hour job, for instance, is $170 . jabari's total fee, f, for a single job is a function of the number, t, of hours it takes him to complete the job. write the function's formula.

For g(x) = 5x - 3 and h(x) = [tex]\sqrt{x}[/tex], find (g · h)(4)

Having a hard time understanding this question (see attachment).