NPV

sir here is a question
a equipment costing 300,000$ with installation cost of 50,000 having useful life of 4years is required.. associated benefits r 100,000$ p.a co uses dtraight line dep n tax rate is 35%. tax allowable dep rate is 25% pn reducing balance method.. calculate npv of the project.. my question is shall we take 300,000 to calculate depreciation allowance or 350,000? plzz clear my point