Question

applying the rules for significant figures
how many significant figures does each value contain?
3.201 milligrams has significant figures.
0.019 miles has significant figures.
0.680 seconds has significant figures.

Explanation:

Step1: Identify significant - figure rules

Non - zero digits are always significant. Zeros between non - zero digits are significant. Leading zeros (zeros before the first non - zero digit) are not significant. Trailing zeros (zeros after the last non - zero digit) are significant if there is a decimal point.

Step2: Analyze 3.201

The digits 3, 2, 0, and 1 are all significant. So 3.201 has 4 significant figures.

Step3: Analyze 0.019

The leading zeros are not significant. Only 1 and 9 are significant. So 0.019 has 2 significant figures.

Step4: Analyze 0.680

The leading zero is not significant, but the 6, 8, and the trailing 0 (since there is a decimal point) are significant. So 0.680 has 3 significant figures.

Answer:

3.201 milligrams has 4 significant figures.
0.019 miles has 2 significant figures.
0.680 seconds has 3 significant figures.