The Court of Tax Review shall hear and determine all protests submitted to it and its decision shall be in writing and filed with the State Auditor and Inspector whose duty it shall be, if no appeal be taken as hereinafter provided, to transmit a copy of such decision to the county clerk, county assessor, and county treasurer, and to the protestant or his attorney of record, and it shall thereupon be the duty of the county clerk to correct the appropriations accordingly, and the duty of the county assessor to so correct the tax rolls if the same have not been turned over to the county treasurer. The district attorney, assisted by the Attorney General at the request of the district attorney, shall represent his county and the municipal subdivisions thereof at the hearing of any protest before said Court of Tax Review, and each county shall pay all necessary expenses of its district attorney in attending any such hearings. No pleadings by the county shall be required and the cause shall be deemed at issue upon the filing of such protest.