The answer is true because if you look at the question what does it say
Answer:
The correct answer is option c.
Explanation:
Formula used to determine an average atomic mass :

Mass of isotope Sb-121 = 120.904 amu
Fractional abundance of Sb-121 = 57.21% = 0.5721
Mass of isotope Sb-123 = 122.904 amu
Fractional abundance of Sb-123 = 42.79% = 0.4279
Average atomic mass of Sb:

Answer:
6 moles of oxygen, or 3O2.
Explanation:
I would build a proportion for this:

I would say that the answer is Sn.
C-is a non-metal
Ge-is a metalliod (consists both non-metal and metal)
Si -is a metalloid
Sn- is a pure metal