Jack pushed and pushed, and finally moved the new refrigerator into the kitchen. what is the best explanation of what happened?
a) jack used energy to do work.
b) jack had no energy and did no work.
c) jack used all his potential energy.
d) jack used energy but the refrigerator did all the work.

If water vapor with the mass of 35.0 grams is cooled and condensed into water in a closed system such as a closed glass jar, what is the mass of the water after the water vapor completely condenses? a) 34.5 grams b) 35.0 grams c) 35.5 grams d) the mass cannot be determined without knowing the volume