please help me on these questions in the picture.

2) Due to friction
3) Because the forces by which bulb is hanged is much greater then the gravity
4) a) By pushing the trolley with more force
b) By pulling the trolley with that force
c) By creating the rightward force more, than the leftone
d) opposite as 4(c)
5) a) Force by the stick causes that
b) It is because white body has transferred it's K.E. into that
c) Because it's rightward force was greater in magnitude than that of left
d) Because white ball hit black ball in that direction