6. Sonic Build Corp. employed Leo and Dan in its cement factory and assigned them the tasks of, among others, directing and supervising rank-and-file employees. Leo and Dan are required to ensure that such employees obey company rules and regulations, and recommend to the company’s Human Resources Department any required disciplinary action against erring employees. There is only one union representing rank-and-file employees. May Leo and Dan join the union? Explain briefly. (5 points)