Alright, let's solve this problem step by step. We have 2004 and 4571 and we're adding them together.

Step 1: We'll start by adding the digits 4 & 1 in column 1 and get 5.

Step 2: We'll start by adding the digits 0 & 7 in column 2 and get 7.

Step 3: We'll start by adding the digits 0 & 5 in column 3 and get 5.

Step 4: We'll start by adding the digits 2 & 4 in column 4 and get 6.

So, 2004 + 4571 = 6575.

