Some economists have alleged that the local market-for nurses' services can be correctly modeled as a monopsony in which there is only a single employer -- the local hospital. a. Explain how the wages and the level of employment of nurses are determined in this case. b. Is the level of employment efficient? Explain carefully. Be clear about the assumptions you are making. c. If the nurses form a union and bargain collectively over wages with the hospital, what are the implications for the level of wages and the employment level for nurses