The notice shall state that:
(a) The assessments have been recorded in the tax collector’s office.
(b) All sums assessed therein are due and payable immediately.
(c) The payment of the sums shall be made to him within 30 days after the date of the first publication or posting of notice, which date shall be stated in the notice.
(d) All assessments not paid before the expiration of the 30 days shall be delinquent, and thereupon 10 per cent of the amount of each such assessment shall be added thereto.