please explain!!

2) An investment navs the following vear-end cash flows: What is the present value of the investment, if its required rate of return is 20% ? 3) AMZN delivered investors a 10% gain during the first, a 15% loss during the second, a 25% gain during the third, and a 5% loss during the fourth quarter of the year. a) What was AMZN investors' buy-and-hold return for the year? b) And their average MONTHLY realized return during the year? a) What was the Buy-and-hold return for the stock with ticker symbol ABVT from closing on Sept 3,2021 to Sept 6, 2021? And for the stock with the ticker LG ? b) What was the buy-and-hold return and what was the return day-by-day for the period Sept 3 , 2021 to Sept 6,2021 for a portfolio that held 1 share of ABVT and 3 shares of LG on Sept 3 ? (Note that once the dividend is paid, it is held as cash in the portfolio)