You work for a nuclear research laboratory that is contemplating leasing a diagnostic scanner $($leasing is a very common practice with expensive, high$-$tech equipment$).$ The scanner costs $$6,500,000.$ Because of radiation contamination, it actually will be completely valueless in four years. You can lease it for $$1,865,000$ per year for four years. Assume that the tax rate is $22$ percent. You can borrow at $6$ percent before taxes. Assume that the scanner will be depreciated as three$-$year property under MACRS. Use Table $10\mathrm{.}7.$

a$.$

What is the NAL of the lease? $($A negative answer should be indicated by a minus sign. Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

b$.$ Should you lease or buy?