Answer:
Atoms X and Atom Y are isotope is right answer
Counting gives an exact number and exact numbers have infinite sig figs.
Answer: c. Some health risks are increased by heredity, which manifest under certain environmental conditions.
Explanation:
Many abiotic factors (non-living factors) such as radiations, hazardous substances present in the environment such as air, water and soil may originate from the industries, mining practices, fossil fuels and landfills. Some of the substances are carcinogenic and mutagenic in nature. These are capable of affecting the genetic make up of the organism. The genetic variations or mutations occurs may transmit from the parent to the offsprings.
Therefore, on the basis of the above information, c. Some health risks are increased by heredity, which manifest under certain environmental conditions. is the correct option.
Answer ; The question is missing in some details, but here are he details ;
The two naturally occurring isotopes of bromine are
81Br (80.916 amu, 49.31%) and
79Br (78.918 amu, 50.69%).
The two naturally occurring isotopes of chlorine are
37Cl (36.966 amu, 24.23%) and
35Cl (34.969 amu, 75.77%).
Bromine and chlorine combine to form bromine monochloride, BrCl.
Explanation:
The detaile calculation is as shown in the attachment.