What is positive and what is negative in disinfection in medicine and the food industry if they use sterilization to kill bacteria?

Iknow #2 is d. i just need to know why

In the lab, ammonia was mixed with water to form ammonium hydroxide. what is/are the reactant(s)? o water and ammonia o ammonia o ammonium hydroxide need

Which is a characteristic of the electron sea model for metallic bonding? molecular orbitals overlap to produce bands. electrons flow easily between metal nuclei. electrons are in fixed positions in the orbitals. atomic nuclei are arranged in an irregular pattern.