Thallium (Tl) belongs to the Group 3 - Boron Family of elements. In the new IUPAC grouping, The Boron family is now Group 13.
Page updated 2/25/2016. Carrier, clerk, mail handlers, and distribution associates are required to take and pass the 473 Postal Exam. Other applicants including motor vehicle operators, mechanic, clerical, electronic technician, machinist, and trades must also pass a written test.
Exam 473 for mail handlers and mail carriers is divided into Parts A through D. Part A covers address checking, or comparing whether two addresses are the same. Part B is forms completion -- the ability to understand and fill out forms used by USPS. Part C has two sections: coding and memory.