方案一：增值税=8000/1.13*0.13-4186.65/1.13*0.13=920.35-481.65=438.85；税金及附加=438.85*12%=52.66；利润总额=8000/1.13-4186.65/1.13-2225-170-730-52.66=196.99；所得税=196.99*25%=49.25；预计净利润=196.99-49.25=147.74 方案二：增值税=10000/1.13*0.13-4186.65/1.13*0.13-1800/1.13*0.13=461.71；税金及附加=461.71*12%=55.41；利润总额=10000/1.13-4186.65/1.13-1800/1.13-2225-170-730-55.41=371.23；所得税=371.23*25%=92.81；预计净利润=371.23-92.81=278.42 方案三：增值税=10000/1.13*0.13-4186.65/1.13*0.13=438.85；税金及附加=438.85*12%=52.66；利润总额=10000/1.13-4186.65/1.13-2000-2225-170-730-52.66=-33.10；所得税=0；预计净利润=-33.10