Answer:
18 miles
Explanation:
The average speed is 6 mph
Melanie ran for 3 hours
Speed × Time = Distance
So, 6 mph × 3 h = 18 miles
Radars are frequently used to identify distance and speed, such as how far away an object is or how fast it is moving. <span>The </span>radar<span> device can then use the change in frequency to </span>determine the speed<span> at which the </span>car<span> is moving. In laser-</span>speed<span> guns, waves of light are </span>used<span> in place of radio waves.</span>