Question

The question are given in image.

Answer 1

X=A sinWt
A=AMPLITUDE
W=ANGULAR FREQUENCY OF OSCILLATION

Answer 2

A piece of stone or a metallic ball suspend with a non stretchble thread make a bob it at position B is rest is callad rest position when it swings it move from B toA back to B fromB to C and back to B this is one completes one oscillation then distance from B to A from B to C is a amplitude