Explain, using simple numerical examples, how it may be possible for a firm to be making (a) zero accounting profit and a positive economic profit; (b) zero economic profit and a positive accounting...

Explain, using simple numerical examples, how it may be possible for a firm to be making (a) zero accounting profit and a positive economic profit; (b) zero economic profit and a positive accounting profit. According to the profit maximising theory of the firm could situations (a) or (b) possibly be equilibrium situations?