Answer:
Tantalium is a Transition metal.
Osmium is a Transition metal.
Thorium is radioactive Metal.
The rule is number your table 1 2. 3 4 5 6 7 0 the number of shells increase as you go further up as it indicates the number of electrons on the outer shell e.g Argon will have 3 electrons on its outer shell hope this helps if not its then tighttt
The oxidation state of N is
B.+5
