3- An agricultural company is considering acquiring a tractor for its production. The ire rate applied is 21%. After a market query, you have two variants for this acquisition (Tractor A and Tractor B). Tractor A Tractor B Acquisition Value 25.000 27.000 Estimated service life 6 years old 8 years old Residual value 1.000 1.000 Maintenance in the 1st year 1.600 1.450 Maintenance in the 2nd year 1.950 1.700 Maintenance in the 3rd year 2.400 2.000 Until the end of life 2.300 2.100 a) Which tractor should the company buy, considering an upgrade rate of 4% per year? Justify your answer. ( 4 values) b) If the upgrade rate of tractor A is 4% and tractor B is 3%, which tractor would you choose? Justify your answer. (3 values),