Utilize the input text as a context reference, choose the right relationship between Jera and Tokyo from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

Cann points to some material combinations already formed or in the works, on all sides of the industry: Shell-BG Group on the supply side, Baker Hughes-Halliburton in services, and on the purchasing side, the powerful Jera combination between Tokyo Electric Power Co and Chubu Electric Power Co.

Answer: headquarters_location