An engineering economics problem

2. A construction firm plans to purchase new excavator. Two manufacturers offered to the company with the respective estimates below. Descriptions Seller A Seller B First cost, PhP (in 1000 Php) 15,000 18,000 Annual M&O cost, Php/ Year (in 1000 Php) 3,500 3,100 Salvage value, Php 1,000 2,000 Economic life, Years 6 9