3. A train 180 m long moving at the speed of 20 m/sec.
over-takes a man moving at a speed of 10m/sec in the same direction. The train
passes the man in
(a) 6 sec
(b) 9 sec
(c) 18 sec
(d) 27 sec
4. The distance between two cities A and B is 330 km. A train
starts from A at 8 a.m. and travels towards B at 60 km/ hr Another train starts
from B at 9 a.m. and travels towards A at 75 km/hr At
what time do they meet?