This number tells scientists how many: pounds hydrogen weighs.
protons hydrogen has in its nucleus.
other elements hydrogen interacts with.
neutrons hydrogen releases in the atmosphere.

The smokey mountains have over 2,100 miles of rushing mountain streams and rivers that flow through the park. in each mile lives a diverse community of native fish, amphibians, insects, and larvae, some of which are found only in the southern appalachians. park managers and scientific researchers test many factors such as fish populations, the watersheds and water tests to determine a) too many lizards are present b) the water quality of the stream c) rainwater is running into local streams d) if visitors to the park are overstaying their welcome