Answer:
5 mph, 90 meters per hour, 270 cm per hour
Step-by-step explanation:
1. 5mph
20 x 0.5 = 10 miles
10 miles divided by 2 hours = 5 miles per hour
2. 90 meters per hour
20 minutes is 1/3 of an hour
30 x 3 = 90 meters in an hour
3. 5.5 cm per minute, 270 cm an hour
65-10 = 55 cm
55 / 10 = 5.5