Let's dive into this subtraction. We'll start with 61045 and subtract 20963 from it.

Step 1: We'll start by subtracting the digit 3 and the borrow 0 from 5 in column 1 and get 2.
2 is the first digit of our result.

Step 2: We'll start by subtracting the digit 6 and the borrow 0 from 4 in column 2 and get -2.
We add -2 to 10 and get 8 as the next digit of the result.

Step 3: We'll start by subtracting the digit 9 and the borrow 1 from 0 in column 3 and get -10.
We add -10 to 10 and get 0 as the next digit of the result.

Step 4: We'll start by subtracting the digit 0 and the borrow 1 from 1 in column 4 and get 0.
0 is the next digit of our result.

Step 5: We'll start by subtracting the digit 2 and the borrow 0 from 6 in column 5 and get 4.
4 is the next digit of our result.

So, 61045 - 20963 = 40082.