Permissible investments means:

(1) Cash;

(2) Certificates of deposit or other debt obligations of a financial institution, either domestic or foreign;

(3) Bills of exchange or time drafts drawn on and accepted by a commercial bank, otherwise known as bankers' acceptances, which are eligible for purchase by member banks of the federal reserve system;

(4) Any investment bearing a rating of one of the three highest grades as defined by a nationally recognized organization that rates such securities;

(5) Investment securities that are obligations of the United States or its agencies or instrumentalities, obligations that are guaranteed fully as to principal and interest by the United States, or any obligations of any state or political subdivision thereof;

(6) Shares in a money market mutual fund, interest-bearing bills or notes or bonds, debentures or stock traded on any national securities exchange or on a national over-the-counter market, or mutual funds primarily composed of such securities or a fund composed of one of more permissible investments as set forth in this section;

(7) Any demand borrowing agreement or agreements made to a corporation or a subsidiary of a corporation whose capital stock is listed on a national exchange;

(8) Receivables that are due to a licensee from its authorized delegates pursuant to a contract described in section 8-2739 which are not past due or doubtful of collection; or

(9) Any other investment or similar security approved by the director.