Scientific Notation Scrap 8

I need help with the following questions:

Part 1: Determine the number of significant digits in each number and write out the specific significant digits.

1. 405000
2. 0.0098
3. 39.999999
4. 13.00
5. 80,000,089
6. 55,430.00
7. 0.000033
8. 620.03080

Part 2: Write the numbers below in scientific notation, incorporating what you know about significant digits.

1. 70,000,000,000
2. 0.000000048
3. 67,890,000
4. 70,500
5. 450,900,800
6. 0.009045
7. 0.023