Final answer:
The provided information does not contain details about the percentage of nurses who use colleagues as a source of information; it focuses on employment numbers and the demand-supply equilibrium in the nursing labor market.
Step-by-step explanation:
The question "What percentage of nurses utilize colleagues or co-workers as a source of information?" does not have a direct answer in the provided information. The details given focus on the number of registered nurses working in a specific geographic area, their employers, and the economic dynamics of demand and supply affecting their labor market. It also mentions a statistical example concerning the likelihood of patients genuinely having the flu based on symptoms. These details, however, do not include data on sources of information that nurses use.