Do not use technology. The figure below shows the graph of the velocity, in feet per second, for a particle moving along the line x = 4. V(1) 3- 2 - 3 (a) During which time interval(s) is the particle doing the following? Enter your answer using interval notation. (i) moving upward (ii) moving downward (iii) at rest (b) What is the acceleration of the particle at the following times? (i) t = 2.31 ft/s2 (ii) t = 4.1 ft / s 2