someone pls help me with my chemistry test plsss my teacher changes the questions so I can't search them up. its 21 questions so I have to upload multiple posts but look at my account to get the rest pls.

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.

How many molecules are found in 1.32 mol of nacl?

This image is an example of a(n) a) atom. b) compound. c) mixture. d) molecule.