Answer: Mixture
Explanation:
Element is a pure substance which is composed of atoms of similar elements.
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present. Example: Air which conatins a mixture of 
, 
, 
and 
Radioactivity another name for radioactive decay. Radioactivity refers to particles emitted from nuclei as a result of nuclear instability.
Answer:
The element is Na
Explanation:
Ionization energy is the energy needed to release the last electron from an atom in its ground state to the gaseous state. It is a periodic property that increases as we go through the periods of the periodic table, but decreases if we move in groups. Sodium has thr ionic radius (another periodic property) that is too large, making it easier to release the electron away, since it is too far from the nucleus.
It’s because thermosetting plastics a very dangerous for the atmosphere idk man srry
