7. Funding a retirement goal: Austin Miller wishes to have $800,000 in a retirement fund 20 years from now. He can create the retirement fund by making a single lump-sum deposit today. a. If upon retirement in 20 years, Austin plans to invest $800,000 in a fund that earns 4 percent, what is the maximum annual withdrawal he can make over the following 15 years? b. How much would Austin need to have on deposit at retirement in order to withdraw $35,000 annually over the 15 years if the retirement fund earns 4 percent