Step 1: Rules for significant figures - All non-zero digits are significant. - Zeros between non-zero digits are significant. - Leading zeros (before the first non-zero digit) are not significant. - Trailing zeros in a decimal number are significant if explicitly shown.
Step 2: Analyze the number 0.00456 Write the number: 0.00456 - Leading zeros: 0.004 (these are not significant). - Non-zero digits: 4, 5, 6 (all are significant). - There are no trailing zeros after the decimal point in this case. So, the significant figures are: 4, 5, 6. Total: 3 significant figures.