QUCKLY PLEASE!! what is a biogeochemical cycle? ​

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

Calculate the molarity of 48.0 ml of 6.00 m h2so4 diluted to 0.250 l .

Which polymers are most closely related? a. protein and nucleic acids b. cellulose and starch c. nucleic acids and starch d. nucleic acids and cellulose