The slow eating of away metal​

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.

The tendency of water molecules to stick together is referred to as a) adhesion b) polarity c) cohesion d) transpiration e) evaporation

Chromosome 17 is made of over million base pairs.