A man has been guarding a house for one hour . Why is it not considered work in science

because there is no displacement or movement in the watchman's work. according to science when displacement or movement take place it is said to be work. hope this helps you.

the current is 0.6

voltage ÷ resistance = current

so 12 ÷ 20 = 0.6

305.7

explanation:

density =m/v

density =917/3.00

density = 305.

approximately = 305.7

in four significant figures