12. A particle travels in a straight line with a constant acceleration of 3 meters per second per second. If the velocity of the particle is 10 meters per second at time 2 seconds, how far does the particle travel during the time interval when its velocity increases from 4 meters per second to 10 meters per second?\\
(A) 20 m\\
(B) 14 m\\
(C) 7 m\\
(D) 6 m\\
(E) 3 m\\