(a) Rivers Limited purchased a machine for $200,000. The machine was depreciated at the rate of 25% per annum using the straight-line method. In order to raise the reported profit, the companys accountant decided to change the depreciation rate to 10% per annum.

(b) Talent Limited is a recruitment agency. On 10 December 2018, Talent Limited helped Ocean Limited hire its Senior Manager and charged the company an agency fee of $30,000. The agency fee was received on 15 January 2019. Talent Limited did not include the $30,000 agency fee in its statement of profit or loss and other comprehensive income for the year ended 31 December 2018.

Q:For each of the above cases, identify the accounting principle or concept that has been violated and give a brief explanation.