Can someone please show me how to do this?

A hockey player is standing on his skates on a frozen pond when an opposing player moving with a uniform speed of 12m/s skates by with the puck. After 3s, the first player makes up his mind to chase his oppponent. If he accelerates uniformly at 4m/s^2, (a)how long does it take him to catch his opponent and (b)how far has he traveled in this time? (Assume the player with the puck remains in motion at constant speed.)

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