Depreciation & Doubtful Debts Q2 20/06/201623/10/2019 Thomas Sim E3009 (20 marks, 2010 Q2) A. (b) Various causes of depreciation. Please refer to 2012 Q8 here. Ref: Angie Ng – answering to Joanna Wee. 2012 Q8 on causes of depreciation.