Answer:
I think u are supposted to find out the are the missing things
Explanation:
Mountain chains are formed by the action of different tectonic plates drifting
Answer:
• The closing of the frontier
Explanation:
• The closing of the frontier• The closing of the frontier• The closing of the frontier• The closing of the frontier• The closing of the frontier• The closing of the frontier• The closing of the frontier
Answer:
All of the elements in a period have the same number of atomic orbitals. For example, every element in the top row (the first period) has one orbital for its electrons. All of the elements in the second row (the second period) have two orbitals for their electrons.
Explanation: