How reading a book demonstrate usage of natural resources

The volume of helium in a blimp is 6.28 x 10^9 millimeters. the density of helium in the blimp is .1786 kilogram/meter^3. find the mass of the helium in the blimp.

What is the percentage composition of carbon in the compound ch4

How do you identify the anode on a power source such as a battery? how do you identify the cathode? how are terms anion and cation?