What is better for measuring how hard you are actually working, Target Heart Rate or Rating of perceived exertion?

Velocity=total displacement/timefrom house to store is 500 from store to neighbor is 200 therefore total displacement=500+200=700metrestherefore,700metres/910seconds=0.8metres per second

Not what goes around on earth but the universe too.

If its history of, then b) because a) implies only present day (now)

It is 5 hope this you out