Turn on the first for one min and then turn it off.! K* u: _- P, G& i8 P# {
Turn on the 2nd for five min and then turn it off.+ o; Y% U4 b5 L7 a
Turn on the 3rd and leave it on.8 h( q( j0 h: s) j/ Q' N
And then go upstairs right away. " t7 e7 M1 x- Y- m6 U% m- K! E- O- V8 |' I9 U
Find the answer by using your fingers and eyes4 Y5 e0 H' C( R' w
这只是一个智力问题,不象是电工问题。
原帖由 老警察 于 2009-1-16 07:12 发表 $ e7 k4 E* Z3 m) J, [. a' n: s( I( MTurn on the first for one min and then turn it off.( X; G2 y6 ^* K, E6 Z- h: i
Turn on the 2nd for five min and then turn it off. / f+ V9 e. d4 d1 Y) Z. m) }Turn on the 3rd and leave it on.1 i! |% H: k8 E6 _
And then go upstairs right away." M3 \% T( a4 h' {9 `" {
+ h/ S) P. e. U6 e& C3 h5 TFind the answer by using ...