What is the units digit in the product of all natural numbers from 1 to 99, inclusive?
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
What is the units digit in the product of all natural numbers from 1 to 99, inclusive?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
0
What is the units digit in the product of all natural numbers from 1 to 99, inclusive?
train