Machines are acquired by Tara Corporation on January 1, 2020 as follows:

EstimatedEstimated

Machine CostResidual Value Service Life

511$27,000$5,00011 years

512$31,000$7,0006 years

513$52,000$10,0007 years

514$32,000$08 years

515$23,000$3,0004 years

Required:

(a) Calculate the composite depreciation rate for this group.

(b) Calculate the average service life in years for this group.

Please provide solution with explanation so that i understand how to do it. Thanks