Round off the following quantities to the indicated number of significant figures. (a) \(7.4855 \mathrm{~g}\) (three significant figures) (b) \(298.693 \mathrm{~cm}\) (five significant figures) (c) \(11.698 \mathrm{lb}\) (one significant figure) (d) \(12.05 \mathrm{oz}\) (three significant figures)

To round off the given quantities to the specified number of significant figures, keep these rules in mind: 1. Non-zero digits (1-9) are always significant. 2. Any zeros between significant digits are also significant. 3. Leading zeros, or zeros at the beginning of a number, are never significant. 4. Trailing zeros, or zeros at the end of a number, are only significant if the number has a decimal point.

Now we will round off each quantity to the indicated number of significant figures using the rules discussed above. (a) \(7.4855 \mathrm{~g}\) (three significant figures) To round off to three significant figures, look at the fourth digit. Since it's greater than 5, the third digit will be increased by 1. Thus, \(7.4855\) is rounded to \(7.49 \mathrm{~g}\). (b) \(298.693 \mathrm{~cm}\) (five significant figures) To round off to five significant figures, look at the sixth digit. Since it's less than 5, the fifth digit remains unchanged. Thus, \(298.693\) is rounded to \(298.69 \mathrm{~cm}\). (c) \(11.698 \mathrm{lb}\) (one significant figure) To round off to one significant figure, look at the second digit. Since it's greater than 5, the first digit will be increased by 1. Thus, \(11.698\) is rounded to \(12 \mathrm{~lb}\). (d) \(12.05 \mathrm{oz}\) (three significant figures) To round off to three significant figures, look at the fourth digit. Since it's less than 5, the third digit remains unchanged. Thus, \(12.05\) is rounded to \(12.0 \mathrm{~oz}\).