Answer:
Emily's average speed is 6 mph and her average velocity is zero.
Step-by-step explanation:
We can calculate the average speed as:
s = (s₁ + s₂) / 2 = (5 mph + 7 mph ) /2 = 12 mph / 2 = 6 mph
s: average speed
s₁: speed in the first 3 laps
s₂: speed in the second 3 laps
And we can calculate the average velocity as:
v = (df - di) / t = (0 m - 0 m) / t = 0 m / t = 0 m / s
v: average velocity
df: final displacement
di: initial displacement
t: time
As Emily is finally in the same place, it doesn't matter the time to finish the 6 laps, we know that the displacement is zero so the average velocity is zero too.