Section 3-28a - Medium-Term Investment Fund(a) There is created a Medium-Term Investment Fund to be administered by the State Treasurer. The State Treasurer may purchase participation units of the fund for all trusts and other funds for which the State Treasurer is responsible for investing. The State Treasurer may sell participation units in the Medium-Term Investment Fund to all agencies, authorities, instrumentalities and political subdivisions of the state. Such participation units are hereby made legal investments for all agencies, authorities, instrumentalities and political subdivisions of the state.(b) All costs of operating the Medium-Term Investment Fund, including the cost of personnel and contractual services, shall be paid from interest earnings of the fund.(c) The State Treasurer is authorized to invest and reinvest funds of the Medium-Term Investment Fund in obligations of the United States government and its agencies and instrumentalities, certificates of deposit, commercial paper, corporate debt securities, savings accounts and bankers' acceptances, repurchase agreements collateralized by such securities, and investment funds or pools comprised of securities in which the Medium-Term Investment Fund may directly invest.(d) The State Treasurer may adopt regulations in accordance with chapter 54 specifying the terms and conditions of the purchase and sale of participation units, the payment of interest, investment policies, and accounting practices.