(710+710)÷(1-710)
=75÷310,
=143(米).
答:这根绳子全长是143米.
_________ smoking, he would not have got cancer in the lung.
A.Was he given up
B.Had he given up
C.Did he give
D.If he gave up
最大屈光力主子午线在何位置称为斜向散光()
A.5°
B.60°
C.90°
D.135°
E.180°