The Commission is hereby authorized to provide by resolution for the issuance of revenue bonds of the District for any one or more of the following purposes: (i) paying all or a part of the cost of all or a part of the project and (ii) refunding any outstanding revenue bonds of the District that have been issued under the provisions of this chapter, including the payment of any redemption premium thereon and any interest accrued or to accrue to the date of redemption of such bonds. The principal of and the interest on such bonds shall be payable solely from the funds herein provided for such payment. The bonds of each issue shall be dated, shall bear interest at such rate not exceeding six percent per year payable semiannually, shall mature at such time, not exceeding 40 years from their date, as may be determined by the Commission, and may be made redeemable before maturity, at the option of the Commission, at such price and under such terms and conditions as may be fixed by the Commission prior to the issuance of the bonds. The principal and interest of such bonds may be made payable in any lawful medium. The Commission shall determine the form of the bonds, including any interest coupons to be attached thereto, and the manner of execution of the bonds, and shall fix the denomination of the bonds and the place of payment of principal and interest thereof, which may be at any bank or trust company within or outside of the Commonwealth. If any officer whose signature or a facsimile of whose signature appears on any bonds or coupons ceases to be such officer before the delivery of the bonds, his signature or such facsimile shall nevertheless be valid and sufficient for all purposes the same as if he had remained in office until delivery. All revenue bonds issued under the provisions of this chapter shall have and are hereby declared to have, as between successive holders, all the qualities and incidents of negotiable instruments under the negotiable instruments law of the Commonwealth. The bonds may be issued in coupon or in registered form, or both, as the Commission may determine, and provision may be made for the registration of any coupon bonds as to principal alone and also as to both principal and interest, and for the reconversion of any bonds registered as to both principal and interest into coupon bonds. The Commission may sell such bonds in such manner and for such price as it may determine to be for the best interest of the District, but no such sale shall be made at a price so low as to require the payment of interest on the money received therefor at more than six percent per year computed with relation to the absolute maturity of the bonds in accordance with standard tables of bond values, excluding from such computations the amount of any premium to be paid on redemption of any bonds prior to maturity. The proceeds of such bonds shall be disbursed for the purposes for which such bonds shall have been issued under such restrictions, if any, as the resolution authorizing the issuance of such bonds or the trust indenture provided for in this chapter. If the bonds of a particular issue, by error of estimates or otherwise, are less than such cost, additional bonds may in like manner be issued to provide the amount of such deficit and, unless otherwise provided in the resolution authorizing the issuance of the bonds or in the trust indenture securing the same, shall be deemed to be of the same issue and shall be entitled to payment from the same fund without preference or priority of the bonds first issued for the same purpose. If the proceeds of the bonds of any issue exceed the amount required for the purpose for which such bonds are issued, the surplus shall be paid into the funds hereinafter provided for the payment of principal and interest of such bonds. Prior to the preparation of definitive bonds, the Commission may, under like restrictions, issue temporary bonds, with or without coupons, exchangeable for definitive bonds when such bonds have been executed and are available for delivery. The Commission may also provide for the replacement of any bond that becomes mutilated or that has been destroyed or lost. Such revenue bonds may be issued without any other proceedings or the happening of any other conditions or things than the proceedings, conditions, and things that are specified and required by this chapter.