Watup everyone? hows life?

How does the space charge width change with forward and reverse bias? also, calculate the space charge width for a reverse bias of 4v on a silicon pn junction at t = 300k and doping concentrations of na = 5x1015cm-3 , nd = 5x 1016 cm-3 .

The graph describes the motion of an object. the object moves with from a to b. it from b to c. it moves with from c to d.

Anybody wanna ? (picture included? )