Which of the following must be the same before and after a chemical reaction? a) the sum of the masses of all substances involved. b) the number of molecules of all substances involved. c) the number of atoms of each type involved. d) both (a) and (c) must be the same.

The post exposure exam follow up must include counseling about the possible implications of the exposure and your infection status including the results and interpretation of all tests and how to protect personal contacts. the follow up must also include evaluation of reported illnesses that may be related to the exposure. what apse should you be provided with?