The structures that an animal uses to exchange gases with its surroundings make up the?

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final

A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?

Which are causes of mechanical weathering? (check all that apply) a. acid rain b. plant growth c. animal actions d. carbon dioxide e. pressure release i chose b & e and got the question wrong.