Use the portion of the periodic table shown at the bottom to answer the questions. Part 1: Name two elements that have the same properties as magnesium (Mg).
Part 2: Determine the number of protons, electrons, and neutrons present in an atom of potassium (K). Explain how you determined your answer using complete sentences.

Part 1 calcium and strontium have same properties as magnesium because all three are in same group.

Part 2 As atomic number of potassium is 19 so it contains 19 protons and 19 electrons because it is neutral

Potassium has 20 neutrons because its mass is 39

We can find neutron = atomic mass - atomic number

Explanation:

c- cold periods in earth's history during which glaciers covered much of the surface.

explanation: