Why is it important for an art conservation scientist to study the properties of a painting before it's repaired?

Can someone me with questions 12 and 13 plz.

Water is initially present in a state where its molecules are far apart. during a change of state, its molecules slow down. which change of state has most likely taken place? from a gas to a liquid from a liquid to a gas from a solid to a liquid from a gas to a plasma

Which scientists contributed to the determination of how cfcs in clouds in the upper atmosphere could destroy ozone molecules