The state Attorney General's Office is asking dozens of questions about the proposed sale of St. Mary's Hospital in Passaic to a California-based for-profit hospital company as part of the review required when charitable institutions are converted to for-profit status. State authorities want to know how Prime Healthcare Services, which operates 21 hospitals and wants to expand into the Northeast, came to bid on St. Mary's, and how the proposals submitted by Prime and other bidders were evaluated. "Why are the trustees willing to accept a commitment from [Prime Healthcare] to maintain the hospital as an acute-care facility for only five years?" asks one of the 50 questions.