What fraction or percentage of carbon atoms has a mass of 12.011 amu?

Zero fraction or percentage of carbon atom has a mass 12.011 amu.

Due to isotopes of carbon, no carbon atom has the mass 12.011 amu. This mass is not the exact mass, but it is the average mass of carbon atoms. Since, the weight of isotopes is different thus, the atomic weight of the carbon in periodic table is written by taking average of atomic weight of isotopes of carbon atoms by also considering their abundance.

right

explanation:

the major pests we deal with are insects, weeds and fungal diseases. a pesticide is a product, whether organic or chemical, used to kill the target pest. there are other techniques gardeners should use that can prevent the severe infestations that make the use of pesticides necessary