Show math please No excel or financial calc

Your small business is considering purchasing one of two different computers. Computer A costs $1,160 today and will increase after-tax revenues by $136 , $400, and $1,223 over years 1-3 respectively. Computer B costs $990 today and will increase after-tax revenues by $677 , $386 , and $147 over years 1-3 respectively. If your firm's financing rate is 15%, what is the cross over rate between these two computers and which should you choose? 21.0% , computer A is the better choice 21.0% , computer B is the better choice 18.2%, computer B is the better choice 24.1% , computer B is the better choice 18.2%, computer A is the better choice 3 Rogue River, Inc. is considering a project that has an initial outlay or cost of $200,000. The respective future cash inflows from its four-year project for years 1 through 4 are: $50,000 , $70,000 , $90,000, and $110,000 respectively. Rogue River uses the internal rate of return method to evaluate projects. Will Rogue River accept the project if its hurdle rate is 11%? 18.93% , reject the project 25.04% , accept the project 21.77% , accept the project 25.04% , reject the project 18.93% , accept the project