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.
Certified mail allows the sender to obtain proof the addressee has received the letter or parcel. Only first class and priority mail can qualify for certification. The United States Postal Service is required to obtain a signature of receipt from the addressee. The signature, time and date of the signing can all be used in a court of law as evidence if necessary. The postal service has made it very easy to check the status of certified mail online. Find your receipt.