A certain neutral atom has an atomic number = 19 and a mass number = 39.Which of the following are correct? 1)It has 19 electrons. 2)It has 20 protons. 3)It has 20 neutrons. 4)It has a total of 39 protons and electrons.
A) 1 and 4 are correct B) 1 and 3 are correct C) 2 and 4 are correct D) 2 and 3 are correct E) 1,3,and 4 are correct