1h=60min=60*60s=3600s
1s=\frac{1}{3600}s
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70m/s = 252 000 m/h= 252 km/h
70\frac{m}{s}=70m:\frac{1}{3600}h=70m*\frac{3600}{1h}=252000\frac{m}{h}=252km/h
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31 m/s = 111 600 m/h \approx 112 km/h
31\frac{m}{s}=31m:\frac{1}{3600}h=31m*\frac{3600}{1h}=111600\frac{m}{h}=111,6km/h\approx112km/h
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32m/s = 115 200 m/h= \approx 115 km/h
32\frac{m}{s}=32m:\frac{1}{3600}h=32m*\frac{3600}{1h}=115200\frac{m}{h}=115,2km/h\approx115km/h
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20m/s= 72 000 m/h = 72 km/h (żle wpisane w treści jednostki 20 m/s ???)
20\frac{m}{s}=20m:\frac{1}{3600}h=20m*\frac{3600}{1h}=72000\frac{m}{h}=72km/h
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510 km/h = 510 000 m/h 142 m/s
510\frac{km}{h}=\frac{510*1000m}{1h}=510000\frac{m}{h}=\frac{510000m}{3600s}=\frac{5100m}{36s}=141,66..\approx 142m/s