Answer:
If the whole trip takes 10 seconds, the SPEED will be (90 + 30) / 10 = 12 m/s
Velocity is vector will depend on the direction of the 30m portion
Step-by-step explanation:
If the 30 m portion is west, then average velocity will be (90 + 30)/10 = 12 m/s west
If the 30 m portion is east, then average velocity will be (90 - 30)/10 = 6 m/s west.
These are the maximum and minimum possible, values between these two are possible for directions having north or south components for the 30 m section.