Carbon 14 has a half-life of 5,730 years. The sample weighs 210 grams. a. After four half-lives, how many grams of carbon-14 remain?

b. After four half-lives, how many years have elapsed?

(Please answer questions a and b.)

Which statements are true about electrolysis? check all that apply. electrolysis requires an acid be present. electrolysis is described by two half-reactions. electrolysis is not an industrial process. electrolysis results in commercially valuable products. electrolysis involves the transfer of electrons. reduction results in the loss of electrons. oxidation results in the loss of electrons.

Which describes fat? a: a carbohydrate that produces energy b: a nucleic acid that directs cell function c: a lipid that stores energy d: a protein that speeds up a chemical reaction

Which of the following words describe the reality that the universe looks the same from various perspective