average speed = total distance / total time

When t = 0, the Icemobile is at (600, 1250).
When t = 30, the Icemobile is at (600, 900).

Find the total distance, or distance between the two points,and the total time.

total distance = √(600 − 600)² + (900 − 1250)² = 350 ft

total time = 30 − 0 = 30 seconds

average speed = 350/30 feet per second

Now try parts (b) and (c).

b: 20 ft/sec
c: 17.68 ft/sec