PC shopping network may upgrade its modem pool. It last upgraded $2$ years ago, when it spent $$170$ million on equipment with an assumed life of $5$ years and an assumed slavge value of $$20$ million for tax purposes. The firm uses stright$-$line depreciation. the old equipment can be sold today for $$120$ million. a new modern pool can be installed today for $$210$ million. this will have a $3-$year life and will be depreciated to zero using stright$-$line depreciation. the new equipment will enable the firm to increase sales by $$22$ million per year and decrease operating costs by $$11$ million per year. at the end of $3$ years, the new equipment will be worthless. assume the firms tax's rate is $30\%$ and the discount rate for projects of this sort is $11\%.$

Required:

a$.$ what is the net cash flow at the time $0$ if the old equipment is replaced?

b$.$ what are the incremental cash flows in years: $($i$)1$; $($ii$)2$; $($iii$)3?$

c$.$what is the NPV of the replacement project?

d$.$ what is the IRR of the replacement project?