Aclosed system changes from state 1 to state 2 while 40kj of heat is added and 60kj of work is done by the system. as system is returned to state 1, 20kj of work is done on it. what is the heat transferred during process 2- show workngs

Which of the following is part of the explanation or description of electromagnetic waves? (select all that apply) a. electrically charged molecules in a medium transfer their energy to nearby electrically charged molecules. b. a changing electric field causes a changing magnetic field. c. magnetic molecules in a medium transfer their energy to nearby magnetic molecules. d. a changing magnetic field causes a changing electric field.