20 miles per hour north is an example of
a) acceleration
b) velocity
c) deceleration
d) speed

B. It's an example of velocity due to the fact that it has a measurement of speed, divided by time, and has a specific direction. Acceleration doesn't have any direction on it, but has speed divided by time. C and D have a different mode of measurement despite of the fact that it still needs meters/miles/km.

Apossible long term health effects of stress would be work