Final answer:
To determine the travel speed, divide 660 miles by 12 hours, which equals 55 miles/hour. Therefore, the correct answer to the question is a- 55 miles/hour.
Step-by-step explanation:
The question asks to solve for the travel speed over a distance of 660 miles in 12 hours. To find the speed, we divide the distance by the time it took to cover that distance. Speed is calculated by the formula:
Speed = Distance ÷ Time
Applying this to the given values:
Speed = 660 miles ÷ 12 hours = 55 miles/hour
Therefore, the correct answer is a- 55 miles/hour. It is important to ensure the unit of speed is consistent with the question, which in this case is miles per hour.