"Three cardinal rules must be remembered in any FOIA case regardless of which exemption is claimed to be applicable. First, the disclosure provisions are to be liberally construed. Second, the exemptions are to be strictly construed. Finally, the party claiming exemption from the general disclosure requirement . . . has the burden of showing the express applicability of such exemption to the material requested." Daily Gazette v. W. Va. Development Office, supra, Syllabus pts. 1 and 2 (citations omitted).