Generally, does the size of a radioactive sample affect half-life?

An electron moved from shell n = 2 to shell n = 1. what most likely happened during the transition? a fraction of a photon was added. a photon of energy was absorbed. a fraction of a photon was removed. a photon of energy was released.

37.0 °c = °f (human body normal temperature)

Name 3 types of energy you see being used as you look around a classroom