A5.5 g sample of a substance contains only carbon and oxygen. carbon makes up 35% of the mass of the substance. the rest is made of oxygen. you are asked to determine the mass of oxygen in the sample. which of the following expressions demonstrates a mathematical procedure to solve this problem using the proper order of operations?

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