Answer:
2,000,000,000.
Step-by-step explanation:
We know that when rounding, we take a look at the digit next to the digit we are rounding. So if I were to ask for you to round 122 to the nearest hundred, then the answer would be 100.
Remember that we round down if the digit next to it is 0-4. If the digit is 5-9, then we round up.
In this case, the digit next to the 2 is a 4. We know that we round down with a 4, so we go to the nearest whole billion, in this case 2 billion.
I hope this helps!