If that's 2398 liters, it's already rounded to the nearest liter. If it's some other unit of measure, you should indicate what it is.
It is 300 when rounded to the nearest hundred
916 rounded to the nearest hundred is 900
5800
0
657 rounded to the nearest ten is 660. 657 rounded to the nearest hundred is 700.
It is already rounded to the nearest hundred thousandths. Rounded to the nearest thousands would be 87.381.
0
10000
0
0
678 is rounded nearest hundred is 700