How does the respiratory filter out particles and keep out food

Which of the following is true of microbes? a. ninety-nine percent of all microbes are pathogenic. b. gene expression in bacteria is very similar to gene expression in humans, which facilitates the use of bacteria in recombinant biotechnology and gene therapy. c. all bacterial enzymes are harmful to humans and the environment. d. microbes create pollutants and toxins that harm the environment.

What is the process of pulling apart an n2 molecule nevermind i got it

Which describes the changes in the earths motion?