Help in physics! help in physics! help in physics! help in physics!?

two cars A and B travel in a straight line. The distance of A from the starting point is given as a function of time by XA(T)=aT+bT^2 with a=2.60m/s and b=1.20m/s^2. The distance of B form the starting point is XB(t)=qt^2 -wt^2 with q=2.80m/s^2 and w=.20m/s^3. Which car is ahead just after they leave the starting point? at what time is the distance from A to B neither increasing nor decreasing? At what time do A and B have the same acceleration?