D = 210 + 120 = 330
S = 54 * 5/18 = 15 mps
T = 330/15 = 22 sec
A train 210 meters long is running with a speed of 54 kmph. The time taken by it to cross a tunnel 120 meters long is?

(a) 29
(b) 22
(c) 48
(d) 99
(e) 11