Answer:
12 m/s
Step-by-step explanation:
Speed is distance moved per unit time and expressed as
S=d/t
S is speed, d is distance and t is time.
When at rest for five minutes, distance moved is zero hence speed is 0/5=0 m/s
When having moved 120 m for 5 s then speed is
S=120/5=24 m/s
Average speed is the average of these two speeda
Average speed=(24+0)÷2=24/2=12 m/s
Therefore, average speed is 12 m/s