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Question A3 (8%) Can a sophisticated decision maker with present bias avoid the preproperation of pleasant activities by using commitment devices? Why? Question A4 (8%) Anna has two friends who owe her money Bhavisha and Winston. Winston owes her 194 which are due today. Bhavisha owes her f100 due in one year from now. When Winston asks for postponement, she asks him to repay f100 in one year. When Bhavisha asks to repay already today and offers her $95, Anna refuses and asks her to pay more. a) Calculate Anna's discount factor in each case. (3%) b) What can you say about Anna's time preferences and how representative is her behaviour? (5%)