competent evidence. Appellees counter that appellants did not object to the lack of an oath given at the joint public hearing; therefore, the argument is waived. Appellees further assert that, should we reach the merits of the argument, there is no requirement in statute, the County Code, or case law that “testimony” at a public hearing like the one in this case be given under oath. Appellees are correct that appellants, many of whom spoke at the joint public hearing without having taken an oath, did not object or otherwise raise the issue at the hearing. Appellants, moreover, remained silent on this subject during the 10-day period in which the “file” remained open for the County Commissioners to receive written materials. “A party who knows or should have 14 Md.App. 615, 691 A.2d 699 (<HOLDING>), cert. denied, 346 Md. 238, 695 A.2d 1227
holding that despite the merits of the argument the appellant raised on appeal the issue was not preserved for judicial review because it was not raised before the administrative agency holding that an issue is preserved for appeal where the issue was sufficiently raised for the court to rule on it   holding that an issue not raised in the trial court cannot be raised for the first time on appeal holding issues not raised before the district court are not preserved for appeal holding that because the appellant did not present to the administrative agency the argument it raised before this court the issue was not preserved and holding that even if preserved the argument failed