Shell Oil Company leased to Flying Tiger Line a gasoline tank truck with a movable ladder for refueling certain types of aircraft. Under the terms of the lease, Flying Tiger was to maintain the equipment in safe operating order, but Shell was obligated to make most of the repairs at Flying Tiger's request. Four years after the lease was entered, Shell, at Flying Tiger's request, replaced the original ladder with a new one built by an undisclosed manufacturer. Both Flying Tiger and Shell inspected the new ladder. Two years later, however, Price, an aircraft mechanic employed by Flying Tiger, was seriously injured when the ladder's legs split while he was climbing onto an airplane wing. What are Price's rights against Shell and Flying Tiger?