Which of the following forces causes comets to regularly return to the inner solar system after being gone for many years? a. friction b. electromagnetic force c. magnetism d. gravity

10 points! will mark brainiest! in a heat engine if 1,000 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 initial energy was 2,000 j 1: write the equation2: 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 energy added you so much!