An object is moving along the x direction with a velocity (in mks units) given by

Question

vx = 3 t^4 − 12 t^3 + 12 t^2 + v0x
Answer the following.
(a) At what three times is the object moving with a constant velocity?
(b) Find the velocity of the object in terms of v0x at each of the above three times.
(c) If the velocity at the middle time is 2 times that of the velocity at the longest time,
how fast was the object moving at t = 0?
(d) How far did the object move in the first second of its motion? State the exact value
here, not a decimal approximation