Explain why charging by friction works better for insulators, while charging by induction works better for conductors

If its history of, then b) because a) implies only present day (now)

Ansa new gas is observed in the form of bubbles;

Gravity, from the center of mass of the box, extending downward normal force, from the floor under the box, extending upward, equal to gravity push force, acting at a point on the box, extending in the direction of motion friction, acting at any point on the box directly opposite the push, extending directly opposite to the motion