:Find the correct statement .15 The short-lived positron-emitting isotopes are produced by a cyclotron immediately before use. The barium is produced by a cyclotron immediately before use. The iodine -containing solutions are produced by a cyclotron immediately before use. All correct.

The correct statement is: The short-lived positron-emitting isotopes are produced by a cyclotron immediately before use.<br /><br />A cyclotron is a type of particle accelerator that is used to produce short-lived positron-emitting isotopes for medical and scientific applications. These isotopes are produced on-demand and have a very short half-life, typically ranging from seconds to minutes. This allows them to be used immediately after production, minimizing the time between their production and their application.<br /><br />The other statements are incorrect. Barium is not produced by a cyclotron immediately before use, and iodine-containing solutions are not produced by a cyclotron either.