A man exerts 500 Newtons of force to move a piece of furniture 2 meters. If it takes him 4 seconds to move the furniture, how much power does it require?

Explanation:

Work = (force) x (distance)

The work he did:    Work = (500 N) x (2m)  =  1000 joules

The rate at which he did it (power):  

Work/time =  1,000J/4s

                  =  250 joules/sec

                  =  250 watts  

Therefore he used 250 watts of power to move the furniture

depends on what you mean by "group." for order, it would be coleoptera (beetles). for class, it would be insecta (insects). for phylum, it would be the arthropoda (animals with jointed exoskeletons).

explanation:

.) the observation by semmelweis that more mothers died of childbed fever when their doctors also worked in the morgue