Answer:
Average speed = 15
Explanation:
To find the speed of the body, we can take the position equation and take the derivative in relation to time:
Speed = dY/dt = 2*3*t = 6t
Then, we need to find the speed at t=0 and the speed at t=5:
Speed(t=0) = 6*0 = 0
Speed(t=5) = 6*5 = 30
Now, we just need to make the average of both speeds:
Average = (0 + 30) / 2 = 15