Tesla appointed Robyn Denholm as new chairman to oversee Elon Musk. Ms. Denholm, the chief financial officer of Australian telecommunications company Telstra Corp., has served on Tesla’s board since 2014 but has fewer ties to Mr. Musk than most of the company’s directors. She takes over as chairman of Tesla effective immediately, Tesla said, and she will continue in her role at Telstra for her six-month notice period. She took responsibility as Telstra finance chief on Oct. 1. Tesla shares rose 0.9% to $351.30 in afternoon trading. Ms. Denholm’s career blossomed in the tech industry. During her years at Juniper, from 2007 to mid-2016, the company’s revenue more than doubled. She was a driving force in Juniper’s 2014 restructuring and turnaround, which led to a record profit in 2015.