A particle moves along the x-axis so that its velocity and acceleration at t=5 seconds satisfy v(5)=0 and a(5)<0. Which of the following best describes the particle’s motion at t=5?
a) The particle will remain at rest because the negative acceleration exactly cancels its velocity.
b) The particle is momentarily at rest and is about to move in the positive x-direction because its velocity will increase.
c) The particle is momentarily at rest and is about to move in the negative x-direction because its velocity will decrease.
d) The particle is moving in the negative x-direction and slowing down.