The hearing on the proposed assessments shall be held by the mayor and city council sitting as a board of adjustment and equalization, at the time and place specified in such notice which shall not be less than twenty days nor more than thirty days after the date of the first publication, unless adjourned. Such session may be adjourned, with provisions for proper notice of such adjournment. At such meeting, the proposed assessment shall be adjusted and equalized with reference to benefits resulting from the improvement and shall not exceed such benefits. If any special assessment is payable in installments, each installment shall draw interest payable annually or semiannually from the date of levy until due. Any delinquent installments shall draw interest at the rate specified in section 45-104.01, as such rate may from time to time be adjusted by the Legislature, from the date of delinquency until paid.