A certain element (X) has isotopes with mass numbers of 10 and 11. The X-10 isotope has an atomic mass of 10.013, and it represents 19.9% of all atoms of this element. The X-11 isotope has an atomic mass of 11.009, and it represents 80.1% of all atoms of this element. Therefore, the average atomic mass, or atomic weight, of this element is __ amu.
Round you answer to the nearest hundredth

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.

sodium i think the chemical element of atomic number 11, a soft silver-white reactive metal of the alkali metal group.

the tricuspid valve is present between right atrium and right ventricle