Answer: A. 45 miles per hour
B. 135 miles
Explanation:
Given: The distance traveled by a car at a constant rate is proportional to the time spent driving.
In the equation
, d represents the distance (in miles) and t represents the time (in hours).

⇒ The constant of proportionality=45 miles per hour.
Also, the distance traveled by car in 1 hour=45 miles
⇒ The distance traveled by car in 3 hours=

∴ A car will travel 135 hours in 3 hours.