22. the main difference between speed and velocity involves
a. direction.
b. weight.
c. distance.
d. gravity.

The main difference between velocity and speed is velocity has direction while speed doesn't

Ke reqd to move from 0 to 50 will be proportional to 50x50 or 2500. this is equal to w.  to change vel from 50 to 150 you need energy prop to 22500 - 2500 = 20,000. this corresponds to 8w.  best answer is a) . work reqd is prop to velocity squared. 

Where is the diagram?