Nuclear medicine injects radioisotopes into the body to diagnose organ function. radioisotopes with short half lives are used so they completely degrade quickly leaving harmless chemicals behind in the body. check the two isotopes are most likely to be used in nuclear medicine.

yttrium-90 has a half life of 7.3 x 10^- 3 years
uranium 238 has a half life of 4.5 x 10^6 years
iodine-131 has a half life of 2.2 x 10^- 2 years
plutonium - 239 has a half life of 2.4 x 10^4 years
cobalt-60 has a half life of 5 years

if two electrons have the same n, the same ℓ, and the same ml, then they are in the same orbital. the pauli exclusion principle states that no two identical fermions (a fancy word for electrons and other subatomic particles like electrons) may occupy the same quantum state in an atom simultaneously.

8 m/s because for him to get the same amount of energy as ray is putting out, bobby, who weighs half as much as ray, needs to run twice as fast.

answers: to make sure that all of the broken pieces of tablet were added to the water, to allow for fair comparison of all three trials, with different particle sizes to avoid experimental error

it is the most commonly accepted one