Answer:15
Step-by-step explanation:
Given
Craftsman sell 10 Jewelry set for $500 each
For each additional set he will decrease the price by $ 25
Suppose he sells n set over 10 set
Earning
Earning 

differentiate to get the maximum value

Equate
to get maximum value



Thus must sell 5 extra set to maximize its earnings.
Answer: 360 square inches
Step-by-step explanation: calculate area by multiplying length by height
The answer is C 8/2=4 and 74/2=37