Do light waves and sound waves need a medium to travel through???

The answer is bhope this

Answer is (d)a brainliest would be appreciated

Answer(false);

The internal energy of the system we can term it as total potential energy and kinetic energy. energy flows out of the surrounding from the system then we can say that the internal energy of the final state is lower than its initials. the sign of  δesystem is negative.δesystem = efinal - einitial=-ve  efinal  ∠einitial.