Leo and Mary Deters owned Deters Tower Service, Inc., in Iowa. Deters Tower serviced television and radio towers and antennas in a multistate area. The firm obtained a commercial general liability policy issued by USF Insurance Co. to provide coverage for its officers, including Leo. One afternoon, Leo and two Deters Tower employees were working on a TV tower in Council Bluffs when they fell from the tower to their deaths. The workers’ families filed a negligence suit against Leo’s estate. USF refused to defend the Deters estate against the suit and pay any resulting claim but did not provide a reason for its refusal. Is USF liable to the Deters estate for this refusal? If so, on what basis might the Deters estate recover, and how much?