(Bloomberg) -- Copper prices plunged below $9,000 a ton in the biggest drop since March 2020 as worries over the impact of a worsening trade war sparked a heavy selloff in metals and mining equities.Most Read from BloombergHousing Agency Aims to Relocate Its DC HeadquartersMetro-North Is Faster Than Acela on NYC-New Haven Route After Signal UpdatesLocal Governments Vie for Fired Federal WorkersLondon Clears Final Hurdle for More High-Speed Trains to EuropeWhat Would ‘Transportation Abundance’ Lo