A. because everything is balanced.
Answer:
1.An element consists of the same kind of atoms while a compound is composed of different kinds of atoms.
2.A monoatomic element cannot be split up physically or chemically but a compound can be split up into new substances by chemical means.
3.Only limited number of elements are known in an element whiles number of known compounds are quite large.
4.The property of an element is the property of the atom whiles the property of a compound is quite different from that of it's constituents.
5 . Elements are represented by symbols and numbers.for example Sodium is represented by Na whiles compounds are represented by their chemical formula.for example,Salt is represented by the formula NaCl.
About 80% of the earth's volume is made of mantle.
<span>The </span>mantle<span> is a layer inside a </span>terrestrial planet<span> and some other </span>rocky planetary bodies<span>. For a mantle to form, the planetary body must be large enough to have undergone the process of </span>planetary differentiation<span> by </span>density<span>. The mantle lies between the </span>core<span> below and the </span>crust<span> above. The terrestrial planets (</span>Earth<span>, </span>Venus<span>, </span>Mars<span> and </span>Mercury<span>), the </span>Moon<span>, two of </span>Jupiter<span>'s </span>moons<span> (</span>Io<span> and </span>Europa<span>) and the </span>asteroid Vesta<span> each have a mantle made of </span>silicate<span> rock.</span><span>Interpretation of spacecraft data suggests that at least two other moons of Jupiter (</span>Ganymede<span> and </span>Callisto<span>), as well as </span>Titan<span> and </span>Triton<span> each have a mantle made of </span>ice<span> or other </span>solid volatile<span> substances </span>up of Mantle
Hope this helped.