You don't have the options, but i would say it means that books can take us to another place mentally and take us away from our problems. Hope it helps !:)
The correct answer to this question is:
"Relative abundance is a comparison between the isotopes and Percent abundance is a comparing the totals." Relative<span> species </span>abundances tend to conform to specific patterns. Percent abundance <span> can be calculated by finding the percentage of an isotope compared to another isotope of an element using its relative atomic mass.</span>
