A vaccum unlike sound,light can travel through any matter including a great vacuum of nothing (space)
Due that the velocity is constant that means that friction force is equal to the force exert by you, otherwise the refrigerator will accelerate or decelerate and in both cases velocity will not be constant.
So then the friction force between refrigerator and floor is 150 Newtons.
Answer:
Action and reaction are equal but act in opposite directions
High energy waves have Gamma rays
