audit risk

Sir, can you please give me feedback over this answer?
risk=the directors review of the useful lives and depreciation rates of all classes of plant and machinery resulted in an overall increase in the asset lives and a reduction in the depreciation charge for the year.

explanation=Reviewing the useful lives of plant and machinery is a highly subjective matter, which is prone to errors. If a valuation expert had not been used, then there is a risk of depreciation being understated and PPE overstated.

response:
Assess the reasonableness of the management’s assumptions over extending the useful lives of the plant and machinery.

Select a sample of machines from the non-current asset register and compare their revised useful life to the useful life of similar machinery of competitors by obtaining information through their FS disclosure notes.

is it too long for 2 marks? how should I improve my answers?