It's possible the answer is petrified fossil
Answer:
covalent bonds
Explanation:
Nitrogen atoms will form three covalent bonds (also called triple covalent) between two atoms of nitrogen because each nitrogen atom needs three electrons to fill its outermost shell.
(if it is still confusing i have another way of explaining so jus let me know :)
Answer:
Highest energy will be equal to 
Explanation:
Charged on doubly ionized helium atom 
It is accelerated with maximum voltage of 3 MV
So voltage 
Now energy is given by 
So highest energy will be equal to 
Answer:
They are averages.
Explanation:
atomic numbers on periodic tables are derived from the average value of all the isotopes of the element. So being averages they are sometimes not integers.