A student throws a set of keys vertically upward to his fraternity brother, who is in a window 3.60 m above. The brother's outstretched hand catches the keys 1.20 s later. (Take upward as the positive direction. Indicate the direction with the sign of your answer.)
(a) With what initial velocity were the keys thrown? m/s
(b) What was the velocity of the keys just before they were caught? m/s