The county assessor shall examine each application for homestead exemption filed with him and shall determine whether or not such application should be approved or rejected and if approved, determine the amount of the exemption. If the application is approved, he shall mark the same “approved” and show thereon the amount of exemption allowed and make the proper deduction upon his assessment rolls. In case he finds that the exemption should not be allowed by reason of not being in conformity to law, he shall mark the application “rejected” and state thereon the reason for such rejection. In any case where the county assessor disallows or reduces an application for exemption, he shall notify the applicant of his action by mailing written notice to him at the address shown in the application, which notice shall be on forms prescribed by the Oklahoma Tax Commission. All applications for exemption, showing thereon the action of the county assessor, shall be delivered to the county board of equalization on or before the fourth Monday of April of each year.