Almost 99% of Earth's atmosphere is made up of two gases. What are the two gases and the percents of each? A)
21% oxygen and 78% nitrogen
B)
21% water vapor and 78% oxygen
09
21% nitrogen and 78% oxygen
D)
21% carbon dioxide and 78% oxygen

100 points answer quick the table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 10 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.

Transportation is the largest single source of air pollution in the united states. air pollution can harm the environment and human health. which technology could offer a solution to this problem? mufflers that reduce noise motors that run on electricity tires that improve gas mileage

One does not belong why? ice, gold ,wood ,diamond and table salt