a vehicle has an initial velocity of 30 meters per second. 30 seconds later it is traveling at a velocity of 60 meters per second. what is the acceleration of the vehicle?
a) 10 meters/second/second in the opposite direction of travel
b) 10 meters/second/second in the same direction of travel
c) -1 meter/second/second in the same direction of travel
d) 1 meter/second/second in the same direction of travel