True, if you move something forward at 100 miles an hour but your on something moving backwards 100 miles an hour you up staying in the same location, aka zero velocity.
Answer:
He traveled 9km
Explanation:
To do this problem you need to use the equation which is Speed= distance/time and this problem gives you the speed which is 18 km/h and it gives you the time 1/2 hour so you write the equation 18= d/ 1/2 which his distance is 9km
<span>In general, as you move across a row in the periodic table, B. atomic radius decreases.
This is because there is a stronger attraction between outermost electrons and nucleus, which is why the radius between them becomes smaller.
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