测量视力时,利用平面镜成像特点可以节省空间.如图所示,让被测

测量视力时,利用平面镜成像特点可以节省空间.如图所示,让被测者面对镜子背对视力表,此人看到视力表的像离他的距离是:                    
 
A.3mB.4mC.5mD.6m

答案

C解析:

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