Here are the answers to your questions:
Question 7: A person involved in criminal activity who gives the police or government agency information but is not actually employed by the police is called a Confidential Informant.
Question 8: When a criminal investigation has not been solved after a long time, it is called a Cold case.
Question 9: According to the differential response strategy, the priority should be given to Call #1: There is a report of an active shooting at the Collierville Mall, as it involves an ongoing threat to life and potential injuries.