Ineed it now plss answer it correctly asap​

Are substances released into the environment that in excess amounts cause damage

All living organisms are composed of a. only one cell. b. at least 100 cells. c. at least three cells. d. one or more cells.

Type the correct answer in each box. use numerals instead of words. if necessary, use / for the fraction bar. the following chemical equation shows the combustion of ethane. balance the equation by filling in the coefficients. c2h6 + o2 → co2 + h2o