2000X20102010-2010X20002000
=2000X(20000000+100000+2000+10)-(2000+10)X(20000000+2000)
=2000X200000+2000X100000+2000X2000+2000X10-2000X200000-2000X2000-10X200000- 10X2000
=2000X100000-10X200000
=200000000-2000000
=198000000