????01????????02????????????????:2.???????25%??????$1000 ???2.?????????10%??????$1000 ???03?????????04????????????05?????????06???????????????25%?????????25%??:1.?????????????????????????????????????2.??????????25%??????$2000 ????? ???3.???????????????+25%?????20????????????:????$1000??????25%????????$1250??????????$1000+$250?×20?=25000??????4.??I