Monopolistic Competition and Oligopoly

1.Using graphs to illustrate your analysis, compare the elasticity values along the monopolistically competitive producer's demand curve with that of:

a.a perfect competitor

b.a pure monopolist.

2.Analyse and explain the meaning of the following: 'A monopolistically competitive producer must look to average variable cost in determining whether or not to produce in the short run, to marginal cost in deciding upon the best volume of production, and to average total cost to calculate profits or losses.' Can you show this algebraically?