EXHIBIT 1.1(B) NUVEEN TAX-FREE UNIT TRUST, SERIES 990 TRUST INDENTURE AND AGREEMENT DATED MARCH 25, 1998 This Trust Indenture and Agreement by and between John Nuveen & Co. Incorporated, as Depositor and The Chase Manhattan Bank, as Trustee, sets...Nuveen Tax Free Unit Trust Series 990 • March 25th, 1998
