Janina, Incorporated, has the following mutually exclusive projects. Year Project A Project B $0$$ $18,000$$ $21,000111,00012,00027,5008,50032,7007,500$ a$-1.$ Calculate the payback period for each project. $($Do not round intermediate calculations and round your answers to $3$ decimal places, e$.$g$.,32\mathrm{.}161.)$ a$-2.$ If the company's payback period is two years, which, if either, of these projects should be chosen? b$-1.$ What is the NPV for each project if the appropriate discount rate is $16$ percent? $($A negative answer should be indicated by a minus sign. Do not round intermediate calculations and round your answers to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$ b$-2.$ Which, if either, of these projects should be chosen if the appropriate discount rate is $16$ percent?