The dead xylem and phloem is called:

pith
root
epidermis
bark

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