$875
2 875 000 000 rounded to the nearest billion is 3 billion.
900
0
853 rounded to the nearest 100: 900. 10853 rounded to the nearest 100: 10900.
600
100
100
0
555 rounded to the nearest 100 is 600.
97 rounded to the nearest hundred is 100. 97 rounded to the nearest ten is 100
100