Andy bought 8 feet of copper pipe at $10.50 per foot. he also bought 5.5 feet of aluminum pipe at $8.25 per foot. explain how to calculate the total cost of andy's purchase. a. step 1 multiply $10.50 by 8 to calculate the cost of the copper pipe. step 2 multiply $8.25 by 5.5 to calculate the cost of the aluminum pipe. step 3 add the two amounts together. b. step 1 multiply $10.50 by 8 to calculate the cost of the copper pipe. step 2 multiply $8.25 by 5.5 to calculate the cost of the aluminum pipe. step 3 subtract the two amounts. c. step 1 divide $10.50 by 8 to calculate the cost of the copper pipe. step 2 divide $8.25 by 5.5 to calculate the cost of the aluminum pipe. step 3 add the two amounts together. d. step 1 divide $10.50 by 8 to calculate the cost of the copper pipe. step 2 divide $8.25 by 5.5 to calculate the cost of the aluminum pipe. step 3 subtract the two amounts.