Suppose investor 1 and investor 2 each has $100 wealth to invest in the two risky assets and the risk-free asset, and suppose that the amount of money investor 1 and investor 2 borrow and lend at the risk-free rate must sum up to zero; that is, there is no outside bank in this economy who lends to investors at the interest rate. In this case, how do you adjust the level of the interest rate so that the total dollar demand from these two investors on the risk-free asset becomes zero