The bonds shall be issued by the state treasurer when authorized by the governor and council. They may be issued at one time or in a series from time to time. The maturity dates of each series shall be determined by the governor and council, but in no case shall they be later than 20 years from the date of issue. The bonds may be redeemable before maturity at the option of the governor and council at such price or prices and under such terms and conditions as may be fixed by the governor and council prior to the issue of the bonds. The bonds shall be in such form and denominations as the governor and council shall determine and, subject to N.H. Rev. Stat. § 6:14 and 6:15, may be nonregisterable or registerable as to principal only or registerable as to both principal and interest. Subject to the provisions of RSA 93-A, they shall be signed by the treasurer and countersigned by the governor. They shall be deemed a pledge of the faith and credit of the state.