8.94 rounded to the thousandth

The decimal part of that number ... the. 94 part ... means 940 thousandths.

The next higher thousandth is 941 thousandths.

The next lower thousandth is 939 thousandths.

Neither of them is any closer to 940 thousandths than 940 already is.

So 8.94 is already written to the nearest thousandth.

8.49 is already rounded to the nearset thousand so just leave it alone