Please help me learn how to solve question three and four.

Equipment with a cost of $220,000 has an estimated residual value of $30,000 and an estimated life of 10 years or 19,000 hours. It is to be depreciated by the straight-line method. What is the amount of depreciation for the first full year, during 3 which the equipment was used 2,100 hours? O A. $21,000 B. $30,000 C. $22,000 DWNA D $19,000 The Weber Company purchased a mining site for $1,750,000 on July 1. The company expects to mine ore for the next 10 years and anticipates that a total of 400,000 tons will be recovered. The estimated residual value of the property is 37 4. $150,000. During the first year, the company extracted 6,500 tons of ore. The depletion expense is 38 39 A. $16,000 40 B. $15,000 41 C. $26,000 42 D. $17,500 43 44