下列长度的单位换算正确的是( )
A:2.5m=2.5m×100cm=250cm
B:75mm=75×10﹣3m=7.5×10﹣2m
C:42cm=42÷100m=0.42m
D:24m=24m÷1000=0.024km
—Many students are unhealthy because of a lack of exercise
—I agree. They should start exercising it's too late.
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