solve in excel and please show all steps

21. A manager must decide berween two comes the manager will take into account Exch machine's operating costs and initial costs, and its breakdown and repair time Machine has a projected verge opening time or 142 hours and a projected average repair time of hours, Projected time for machine B are an average operating time of 6 hours and it repur time of 2 hours What are the projected valabilities ar cach machine! art by percentages of 54. birdes the use 21. A manager must decide between two machines. The manager will take into account each machine's operating costs and initial costs, and its breakdown and repair times. Machine A has a projected average operating time of 142 hours and a projected average repair time of 7 hours Projected times for machine B are an average operating time of 65 hours and a repair time of 2 hours. What are the projected availabilities of each machine? darinnar ertimates that she can increase the average time between failures of a part by 5 percent at a cost of $450, or (b) reduce the average 100 hand