To determine the number of significant digits in the measurement [tex]\(0.0090 \, \text{mL}\)[/tex], follow these steps:
1. Identify Significant Digits Rules:
- All non-zero digits are significant.
- Leading zeros (zeros before the first non-zero digit) are not significant.
- Captive zeros (zeros between non-zero digits) are significant.
- Trailing zeros in a decimal number are significant.
2. Analyze the Number:
- The number [tex]\(0.0090 \, \text{mL}\)[/tex] has leading zeros before the 9.
- These leading zeros (0s before the 9) are not significant as they only serve to place the decimal point.
- The digit 9 is significant.
- The trailing zero after the 9 is significant because it is after a decimal point and indicates precision in the measurement.
3. Count the Significant Digits:
- The first significant digit is 9.
- The second significant digit is the trailing zero after 9.
- Hence, [tex]\(0.0090 \, \text{mL}\)[/tex] has two significant digits (9 and 0).
Thus, the number of significant digits in [tex]\(0.0090 \, \text{mL}\)[/tex] is:
d) 3.