Turn on the first for one min and then turn it off.$ N8 R8 r8 B" c' Y: p R7 M. e" Z
Turn on the 2nd for five min and then turn it off. ! {3 i" D7 W7 PTurn on the 3rd and leave it on.9 I% Y1 u# `3 n& l7 ]* p/ I5 C( q
And then go upstairs right away.( Y+ r7 X0 P/ c+ Y F8 e3 U
: ~3 A2 l9 n# x S2 SFind the answer by using your fingers and eyes 7 N3 I, d6 {2 S) m) l) Q1 A- S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 + D1 |+ s1 Y2 c0 ^Turn on the first for one min and then turn it off. ; ^* D! F+ _- g* MTurn on the 2nd for five min and then turn it off.; m4 {( [7 V( c7 A# R# L4 w5 I2 `# V2 ^" X
Turn on the 3rd and leave it on. S! |8 g: H' b% \! Z7 j+ r1 t' V4 G+ ~
And then go upstairs right away.0 W! h k3 W2 f: ?8 D; X/ [