This can also be answered by binomial theorem:

=(9? )^ 100 1

=9^2002

=( 10 - 1)^2002

Because all other items are greater than 10 4, the last four items are:

= 1^2002 - 2002 * 10 + (2002*200 1/2! )* 10? - (2002*200 1*2000/3! )* 10?

= 1 - 20,020 + 200,300, 100 - 1,335,334,000,000

Although the last number is large and negative, the last six digits must still be 0 when subtracting from the high position, which has no effect on our answer. Therefore, we only need to care about the sum of the first three items.

=200,280,08 1

So the last four digits are 008 1.