In 1808, John Dalton proposed a series of statements regarding the atom that became known as Dalton's atomic theory. Since Dalton's original proposal, some of the statements have been updated or changed due to new discoveries. Which discovery is the reason why Dalton's assumption that all atoms of the same element have the same mass and other properties is no longer valid

Listenbase your answer to the question on the information below.nuclear radiation is harmful to living cells, particularly to fast-growing cells, such as cancer cells and blood cells. an external beam of the radiation emitted from a radioisotope can be directed on a small area of a person to destroy cancer cells within the body.cobalt-60 is an artificially produced radioisotope that emits gamma rays and beta particles. one hospital keeps a 100.0-gram sample of cobalt-60 in an appropriate, secure storage container for future cancer treatment.which choice represents the correct product for the beta decay of the co-60? fe-60ni-60fe-61ni-61