Any help would great....thank you?

Par Value = $1000 Time to Maturity Bid Asked (days) 1.51 60 1.6 1.61 88 1.52 1.62 116 1.53 172 1.64 1.55 respectively? 2. What would be the effective annual rate of return on your investment if you held the bill until maturity? (for all three bills) 3. Which T-bill will you invest in? Assume you will hold it to maturity. 4.What would be the EAR if you bought this bill today and sell it back to a dealer after 84 days, assuming that yields do not change over time