A schedule of machinery owned by Ajman Co presented below: Estimated Total Cost Salvage Value Machine X $420,000 $42,000 Machine Y 225,000 22,500 Machine Z 492,000 24,000 Estimated Life in Years 10 5 12 19. What is the composite rate of depreciation (in percent) for these assets? I 20. What is the composite life (in years) for these assets