Final answer:
Significant figures communicate measurement accuracy in scientific notation. Non-zero digits, zeros between non-zeros, and trailing zeros after a decimal are significant. Leading zeros are not significant.
Step-by-step explanation:
The question pertains to the rules for determining significant figures in numerical values.
Significant figures are vital in scientific notation because they convey the precision of a measurement.
The rules mentioned in your question allude to how to count significant figures:
All non-zero digits are considered significant (rule 1).
Zeros between non-zero digits are significant (rule 2).
Leading zeros are not significant (rule 3).
Trailing zeros in a number containing a decimal point are significant (rule 5).
The example includes a number with a trailing zero, which is considered significant according to rule 5, implying the number has been measured to that decimal place.
Reasoning Behind Significance
Understanding the significance of each digit is necessary for correctness in scientific calculations.
Exactness is crucial, as rounding can alter the meaning.
For example, if a number ends in an 8, the preceding digit is rounded up accordingly (exhibited in rule adjustments provided).