If one H2O molecule contains 2 hydrogen atoms and 1 oxygen atom, and 10 H2O molecules contain 20 hydrogen atoms and 10 oxygen atoms, how many hydrogen atoms and oxygen atoms are contained in 6.02 times 1023 H2O molecules? The star named Alpha Centauri is 4.3 light-years from the Earth. If 1 light-year is approximately 6 times 109mi, how far is Alpha Centauri? If the county of Queens, New York, has a population of approximately 2,200,000 and the area is 110 mi2, how many people are there per square mile? If the county of Catawba, North Carolina, has a population of approximately 150,000 and the area is 400 mi2, how many people are there per square mile? According to the Federal Emergency Management Agency (FEMA), the annual loss due to earthquakes in California is approximately $3.5 times 109. If this is representative as a yearly average, find the loss over 15 yr.