Answer:
pairs
Step-by-step explanation:
Given
Profit on selling 'x' pairs of shoes is 
Find the derivative of the function to find out the critical points

Thus, for 4 pair of shoes profit is maximize.
Answer:
What's the purpose? ................
If you’re looking for profit is would be $59.00
Answer:
63
Step-by-step explanation:
(6+9÷3)×7
division is always first
(6+3)×7
then parenthesis
9×7
multiply
63