well, do a payments table of values, just like before for each mont hmm let's see
1st month.......................3500 + p(1)
2nd month....................3500 + p(2)
3rd month.....................3500 + p(3)
4th month.....................3500 + p(4)
5th month.....................3500 + p(5)
36th month..................3500 + p(36)

Answer:
It is 39 cupcakes.
Since he charges $2 per cupcake (39), it is 78.
He makes profit so subtract 30 from 78 and you get $48.
The sides of a triangle must satisfy the triangle inequality, which states the sum of the lengths of any two sides is strictly greater than the length of the remaining side.
We really only have to check if the sum of the two smaller sides exceeds the largest side.
A. 5+6>7, ok
B. 6+6>10, ok
C. 7+7=14 Not ok, this is a degenerate triangle not a real triangle
D. 4+6>8 ok
Answer: C