请问这里为什么扣除的是差值？

NO.PZ2018062018000052问题如下Company M purchasea $500,000 equipment with a 5-yeuseful life the beginning of 2016, consiring the salvage value is zero. The equipment wcapitalizeanpreciateon straight-line metho the enof 2016, enng shareholrs’ equity of company M is 15,000,000, the trate is 27%, net income is 900,000, no vinis taken into account. All else equal, if the equipment were expenserather thcapitalize company M's return on equity the enof 2016 woulbe:A.6.3%.B.4.1%.C.5.6%. B is correct.If the equipment were expenserather thcapitalize company M’s net income anshareholrs’ equity woul$292,000 lower thbefore: ($500,000-$500,000/5)× (1-27%) = $292,000ROE=Net  incomeShareholr′s  equity=900,000−292,00015,000,000−292,000=4.1%ROE=\frac{Net\;income}{Shareholr's\;equity}=\frac{900,000-292,000}{15,000,000-292,000}=4.1\%ROE=Shareholr′sequityNetincome​=15,000,000−292,000900,000−292,000​=4.1% 为什么对NI的影响是减少了100000*（1-27%）；1-27%是为什么

NO.PZ2018062018000052 问题如下 Company M purchasea $500,000 equipment with a 5-yeuseful life the beginning of 2016, consiring the salvage value is zero. The equipment wcapitalizeanpreciateon straight-line metho the enof 2016, enng shareholrs’ equity of company M is 15,000,000, the trate is 27%, net income is 900,000, no vinis taken into account. All else equal, if the equipment were expenserather thcapitalize company M's return on equity the enof 2016 woulbe: A.6.3%. B.4.1%. C.5.6%. B is correct.If the equipment were expenserather thcapitalize company M’s net income anshareholrs’ equity woul$292,000 lower thbefore: ($500,000-$500,000/5)× (1-27%) = $292,000ROE=Net  incomeShareholr′s  equity=900,000−292,00015,000,000−292,000=4.1%ROE=\frac{Net\;income}{Shareholr's\;equity}=\frac{900,000-292,000}{15,000,000-292,000}=4.1\%ROE=Shareholr′sequityNetincome​=15,000,000−292,000900,000−292,000​=4.1% 如果要是费用化的话，这个机器的总值500，000不就应该是减去的费用吗？要算ni的时候就应该是900,000-500,000*（1-t）啊，为什么要乘上1/5？

NO.PZ2018062018000052 问题如下 Company M purchasea $500,000 equipment with a 5-yeuseful life the beginning of 2016, consiring the salvage value is zero. The equipment wcapitalizeanpreciateon straight-line metho the enof 2016, enng shareholrs’ equity of company M is 15,000,000, the trate is 27%, net income is 900,000, no vinis taken into account. All else equal, if the equipment were expenserather thcapitalize company M's return on equity the enof 2016 woulbe: A.6.3%. B.4.1%. C.5.6%. B is correct.If the equipment were expenserather thcapitalize company M’s net income anshareholrs’ equity woul$292,000 lower thbefore: ($500,000-$500,000/5)× (1-27%) = $292,000ROE=Net  incomeShareholr′s  equity=900,000−292,00015,000,000−292,000=4.1%ROE=\frac{Net\;income}{Shareholr's\;equity}=\frac{900,000-292,000}{15,000,000-292,000}=4.1\%ROE=Shareholr′sequityNetincome​=15,000,000−292,000900,000−292,000​=4.1% Company M purchasea $500,000 equipment with a 5-yeuseful life the beginning of 2016, consiring the salvage value is zero. The equipment wcapitalizeanpreciateon straight-line metho the enof 2016, enng shareholrs’ equity of company M is 15,000,000, the trate is 27%, net income is 900,000, no vinis taken into account. All else equal, if the equipment were expenserather thcapitalize company M's return on equity the enof 2016 woulbe:

NO.PZ2018062018000052 问题如下 Company M purchasea $500,000 equipment with a 5-yeuseful life the beginning of 2016, consiring the salvage value is zero. The equipment wcapitalizeanpreciateon straight-line metho the enof 2016, enng shareholrs’ equity of company M is 15,000,000, the trate is 27%, net income is 900,000, no vinis taken into account. All else equal, if the equipment were expenserather thcapitalize company M's return on equity the enof 2016 woulbe: A.6.3%. B.4.1%. C.5.6%. B is correct.If the equipment were expenserather thcapitalize company M’s net income anshareholrs’ equity woul$292,000 lower thbefore: ($500,000-$500,000/5)× (1-27%) = $292,000ROE=Net  incomeShareholr′s  equity=900,000−292,00015,000,000−292,000=4.1%ROE=\frac{Net\;income}{Shareholr's\;equity}=\frac{900,000-292,000}{15,000,000-292,000}=4.1\%ROE=Shareholr′sequityNetincome​=15,000,000−292,000900,000−292,000​=4.1% shareholr's equity 为什么还需要减呀？

NO.PZ2018062018000052问题如下Company M purchasea $500,000 equipment with a 5-yeuseful life the beginning of 2016, consiring the salvage value is zero. The equipment wcapitalizeanpreciateon straight-line metho the enof 2016, enng shareholrs’ equity of company M is 15,000,000, the trate is 27%, net income is 900,000, no vinis taken into account. All else equal, if the equipment were expenserather thcapitalize company M's return on equity the enof 2016 woulbe:A.6.3%.B.4.1%.C.5.6%. B is correct.If the equipment were expenserather thcapitalize company M’s net income anshareholrs’ equity woul$292,000 lower thbefore: ($500,000-$500,000/5)× (1-27%) = $292,000ROE=Net  incomeShareholr′s  equity=900,000−292,00015,000,000−292,000=4.1%ROE=\frac{Net\;income}{Shareholr's\;equity}=\frac{900,000-292,000}{15,000,000-292,000}=4.1\%ROE=Shareholr′sequityNetincome​=15,000,000−292,000900,000−292,000​=4.1% 感觉唯一需要考虑的点就是100，000。对于tax的计算还是不太明白。