Does anyone know the answer to both these questions ???

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.

Explain why the factor 1.5 is broke. into two numbers in the model.

9/10 divide by -3/15 as a mixed number