On 1 January 2011 Z Ltd purchased a photocopier for cash consideration of $300 000. The copier has a $nil estimated scrap value. Z Ltd expects to use the photocopier for 5 years. Z uses the units of production method record depreciation on the photocopier. The photocopier is expected to produce 100 million of paper copies over its useful life. In the year to 31 December 2011, Z Ltd produces 15 million copies. In the year to 31 Decener 2012, Z produces 35 million copies. The annual depreciation expense for 2011 is calculated as follows: Select one: a. $60 000 b. $75 000 c. $105 000 d. $45 000