(1) (c).
(b) “Public improvement” has the meaning given in s. 66.0713 (1) (d).
(2) Every bid received for any public improvement which is not to be paid wholly in cash shall contain a provision that all payments made in cash by the local governmental unit as provided by contract or made on special assessments are subject to a specified rate of discount. The treasurer of the local governmental unit shall issue a receipt for every payment made on any special assessment, stating the date and amount of the cash payment, the discount and the total credit including the discount on a specified special assessment. The treasurer shall on the same day deliver a duplicate of the receipt to the clerk, who shall credit the specified assessments accordingly. All moneys so received shall be paid to the contractor as provided by the contract.