Charles knows that adding salt to water causes the freezing point of water to be lowered, but he wants to know if rock salt affects the freezing point more than table salt. Charles performed an investigation in his classroom in which he measured the freezing point of 250 mL of water. He used this measurement as his control. Then, he dissolved equal amounts of rock salt and table salt in two identical 250 mL beakers of water. Finally, he measured the freezing points of each beaker of water, analyzed his results, and formed a conclusion.

What type of investigation did Charles perform?

answer;

medical directors

explanation;

medical directors grants and supervises the privilege or permission to use an aed on an ambulance.

other roles of a medical director includes;

-provide medical leadership, including coordination with local ems and 911 centers.

-provide guidance in equipment selection and deployment

-develop guidelines for responder actions

-oversee medical care that is rendered through the program, including review of all responses to medical emergencies

-ensure appropriate initial training and skill maintenance

-assume overall responsibility for the conduct and operation of all patient care related activities