A train of length 180 m travelling at 72 kmph overtook a motorcyclist travelling at 36 kmph at 4 p.m. At 5 p.m it overtook another cyclist travelling in the opposite direction at a speed of 18 kmph.When will the cyclist meet the motorcyclist?
a)1 hr 20 mins b)1 hr 30 min c)1 hr 45 min d)none of the above