ans is Eighteenth-century national security focused on military defense from threats posed by European armies while 21st-century national security must address non-military threats, including those inside the country’s borders.
Answer:
1.Strong attraction between two or more atoms.
2.Hold atoms in molecules and crystals together.
Explanation:
Hope this help you...
It's physical state. like weather it's liquid or solid or gas.
too much to explain and not enough space to write down