8. (4 points) A particle moves according to a law of motion s(t) = -3t' + 3t + 1,t 2 0, where t is measured in seconds and s in meters. a. Find the velocity at time t. b. When is the particle moving in the positive direction? c. Find the distance that the particle travels in the first 1 second. d. Find the acceleration at time t. e. When is the particle speeding up?13. (8 points) Consider the following Riemann sum: lim 72-00 i=1 a. Find the limit of the Riemann sum directly. b. To which integral does the Riemann sum correspond