eh. u might lame leh. 1st way, say is say slowly la. nice to
see. but if realli litdat. u think pple wun dulan? 2nd way, sensor,
sensor put whr? on track? if a bird just happen to fly till there
how? what if pple drop items on to e track? stop e whole mrt? n
somemore, even if put sensor, pple jump down liao, mrt power
connection break. u noe what is breaking distance? u mrt is so long
n heavy, u got study physics? u noe what is force? 3rd, put
mirrors, u think so easy? put whr? let pple see upskirt ar? pls
think b4 u talk. tis was one of our secondary projects so many year
ago. n we came up with better things than urs. -.-