Does anyone know the problem with apx physics semester 2 unit 1 Electricity and Magnetism Wrap-Up 1.5.2 Test (CST)? Please help me thanks

Which object is most likely represented by a dot?

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

Carbon 14 is a naturally occurring stable