Robert drove at an average speed of 60 miles per hour for 6 hours. nancy drove for 7 hours at an average speed of 56 miles per hour. which method shows a way to calculate the difference in the distances they drove? a. step 1 divide: 60 ÷ 6.step 2 divide: 56 ÷ 7. step 3 subtract the two quotients. b. step 1 divide: 60 ÷ 6. step 2 divide: 56 ÷ 7. step 3 add the two quotients. c. step 1 multiply: 60 × 6. step 2 multiply: 56 × 7. step 3 add the two products. d. step 1 multiply: 60 × 6. step 2 multiply: 56 × 7. step 3 subtract the two products.