Troy bought 117 feet of white rope and 162 feet of yellow rope. He wanted to cut each rope into 9 equal pieces. Explain how to calculate the difference in length between one piece of white rope and one piece of yellow rope.

A. Step 1: Multiply: 117 by 9. Step 2: Multiply: 162 by 9. Step 3: Add the two products.

B. Step 1: Multiply: 117 by 9. Step 2: Multiply: 162 by 9. Step 3: Subtract the two products.

C. Step 1: Divide: 117 by 9. Step 2: Divide: 162 by 9. Step 3: Subtract the two quotients.

D. Step 1: Divide: 117 by 9. Step 2: Divide: 162 by 9. Step 3: Add the two quotients.