3
Circumference is 2πr, and the large cake has a radius 3 times the radius of the small cake. So, the circumference of the large cake will be 3 times that of the small cake.
So this would be a cubic graph because the largest exponent is a 3.
The Y-intercepts can be found by making all the x's equal 0, so then that would end up being -96 (makes sense considering a cubic graph intercepts at the origin, and this graph moves it down 96 units.
The X-intercepts (the zeros) are a bit tricky. We know that there will likely be three zeros because the exponent is a three. The zeros for this graph are 3, 4, and 8
So in Summary:
This is a Cubic graph with X-intercepts at (3,0), (4,0) and (8,0) and with Y-intercept at (0,-96)
Monday . . . . . 2.5 miles
Tuesday . . . . . 4.6
Thursday . . . . 6.75
Saturday . . . . . 4.8
Total = 18.65 miles
Days per week = 4
Average miles per running day = 18.65/4 = 4.6625 miles
Rounded to the nearest 0.01 = 4.66 miles per running day