Answer:
it' should be 0.15 have a great day
So I think the answer to m<5 is 75 degrees
Average rate of change is defined by (y^-y)/(t^-t) where the ^ means the final(so final y and final t)
So you'd do (8.75-2.75)/(12-4) which is 6/8 which is 3/4 of a dollar per week
