# 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 To solve this question, let us remember the basic rules of what counts as a significant figure or digit:

Rule One: All non-zero digits are significant.

Rule Two: All zeroes between significant digits are significant.

Rule Three: All zeroes which are both to the right of the decimal point and ...

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To solve this question, let us remember the basic rules of what counts as a significant figure or digit:

Rule One: All non-zero digits are significant.

Rule Two: All zeroes between significant digits are significant.

Rule Three: All zeroes which are both to the right of the decimal point and to the right of all non-zero significant digits are significant.

Now, let's solve each part individually:

1) 405000: The number of significant digits is 3, and the digits are 4, 0, and 5. Using Rule One, the digits 4 and 5 are significant. Using Rule Two, the zero between 4 and 5 is significant. Similarly, using Rule Three, the last three zeroes are non-significant.

2) 0.0098: The number of significant digits is 2 (only 9 and 8 are significant; the zeroes to the right of the decimal point are not to the right of non-zero significant digits). The significant digits are 9 and 8.

3) 39.999999: The number of significant digits is 8. (Hint: all the non-zero digits are significant). The significant digits are 3, 9, 9, 9, 9, 9, 9, and 9.

4) 13.00: The number of significant digits is 4 (the zeroes to the right of the decimal point are significant). The significant digits are 1, 3, 0, and 0.

5) 80,000,089: The number of significant digits is 8 (hint: Rule Two: zeroes between significant digits are always significant). The significant digits are 8, 0, 0, 0, 0, 0, 8, and 9.

6) 55,430.00: The number of significant digits is 7 (hint: Rule One and Rule Three). The significant digits are 5, 5, 4, 3, 0, 0, and 0.

7) 0.000033: The number of significant digits is 2 (hint: Rule One and Rule Three). The significant digits are 3 and 3.

8) 620.03080: The number of significant digits is 8. The significant digits are 6, 2, 0, 0, 3, 0, 8, and 0.

Hope this helps.

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