Answer:
5.697
Explanation:
The nearest thousandth is the third-place value after the decimal point. In order to round any given number look to the number to the right of the given place value (in this case thousandths). If the number is greater than or equal to 5 then you can round the number up once, if it is less than 5 you do not round up at all.

Therefore the answer to your question is 5.697.
I hope this helps.