Hey there, I have a Acid base titration lab due tmr and I don't understand these 4 questions can someone please help me out. ASAP I will really appreciate it

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.

Which atom or ion is the largest? 0 a. 0 0 0 0 e. li

Which of the following shapes would represent a molecule with two bonded atoms and 3 lone pairs on only one of them , trigonal planar , bent , trigonal pyramidal , linear