A 70-year-old recently retired engineer is discussing with you, over coffee, whether to gift $600,000 to-day to his only daughter or invest the $600,000 and bequeath the $600,000 plus earnings to his daughter in his will. The engineer expects to live another 15 years. What would you advise the engineer to do? Carefully explain your reasoning and make explicit any assumptions you make, such as taxes, earnings rates, spending patterns, and so on.