Irwin rode his bicycle from one end of a trail to another and back at a speed of 20 miles per hour. If the trail is 4 miles long, for how many hours was Irwin riding? 0.2 hours
0.4 hours
2.5 hours
5.0 hours
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The maximum distance (in nautical miles) that a radio transmitter signal can be sent is represented by the expression 1.23h√, where h is the height (in feet) above the transmitter. estimate the maximum distance x (in nautical miles) between the plane that is receiving the signal and the transmitter. round your answer to the nearest tenth.