(a) Briefly explain why a bank run may occur to a healthy bank with positive net worth just because of rumors about the bank. Also, explain briefly why a deposit insurance may help in preventing bank run. (b) Based on the loanable fund market model introduced in this course, if people become more optimistic about future profits of business, while they also expect to earn a higher personal income in the future, how do these affect the demand and supply of loanable fund, and the equilibrium real interest rate? (c) One important way that a central bank conducts its monetary policy is to affect the interest rate of the over-night interbank loan market. Explain how a reduction of the interest rate in the over-night interbank loan market would affect the general loanable fund market and thus the investment demand of the economy