Chapter 1 - Whole Numbers - 1.1 Reading and Writing Whole Numbers - 1.1 Exercises - Page 8: 10

billions - 100 millions - 258 thousands - 100 ones -006

The first group of three digits from right to left is the ones period. The thousands period is the second group of three digits from the right. The millions period is the third group of three digits from the right. The billions period is the fourth group of three digits from the right.