Displacement, Velocity, and Acceleration Practice Test

A particle moves along the x-axis with a velocity given by $$v_x(t) = 4t^3 - 2t$$. If the particle is at $$x=1$$ at time $$t=1$$, what is its position at time $$t=2$$?

An object's position is given by the function $$x(t) = 2t^3 - 15t^2 + 36t - 8$$. At which of the following times is the object momentarily at rest?