Answer:
1 has the highest density because it has the most amount of circles in the least amount of space- it is the most densely filled with circles; it is the most dense.
Answer:
The number of neutrons is entirely dependent on the Mass number of the particular atom. The standard mass for potassium is 39.
Potassium is element number 19, so it has 19 protons and 19 electrons in the neutral atom. It has therefore 39-19 = 20 Neutrons.
Explanation: