In Du Page County Board of Review v. Department of Revenue, 339 Ill. App. 3d 230, 790 N.E.2d 918, 274 Ill. Dec. 145 (2003), this court addressed whether a house for a church's schoolteachers was used exclusively for religious purposes, making it exempt from taxation. While acknowledging that the clearly-erroneous test is less than well defined, we agreed that the supreme court has rewritten the rules for reviewing administrative agencies' decisions. Du Page County Board of Review, 339 Ill. App. 3d at 234. In that case, we determined that the exemption issue involved a mixed question of law and fact and applied the clearly-erroneous standard of review. Similarly, in Ogden Chrysler Plymouth, Inc. v. Bower, 348 Ill. App. 3d 944, 809 N.E.2d 792, 284 Ill. Dec. 226 (2004), we addressed whether payments a car dealer received from a car manufacturer as part of an employee incentive program constituted "gross receipts" subject to taxation. Ogden Chrysler Plymouth, 348 Ill. App. 3d at 947. The Court stated that this issue involved a mixed question of law and fact. Ogden Chrysler Plymouth, 348 Ill. App. 3d at 950. The issue partly involved legal questions of statutory interpretation, such as whether the payments constituted gross receipts. Also, the issue was partly factual because it involved determining whether the facts, such as the structure of the employee incentive program, supported the Department's finding that the payments constituted part of the consideration for the relevant transactions. Ogden Chrysler Plymouth, 348 Ill. App. 3d at 950.