Over the past three decades about half of the public firms were regular dividend payers, while the other half were not paying dividends at all. Assuming wealth maximization of shareholders is a primary objective of the management, explain: a) why some firms choose to pay dividends consistently (give at least three possible reasons); b) why other firms choose not to pay any dividends at all (at least three reasons); c) why some other firms choose to combine stock repurchases and cash dividends (at least three reasons).