Megan let her wagon outside what was raining and filled with water. When Megan tried to move the wagon that afternoon, she failed to budge the wagon. Why did Megan's wagon become hard to move?

In a heat engine of 1000 j of heat enters the system and the piston does 500 j of work what is the final internal energy of the system if the inital energy was 2000 j we have to do all of these down here 1)write the equation 2)list out your know variables 3)plug the numbers into the equations 4)solve 5)write your solution statemtn that includes inital energuy and final energuy added