<prompt> The London Metal Exchange LME ndiyo futures exchange pamwe guru munyika musika mune mikana uye neramangwana zvibvumirano pamusoro chawo uye dzimwe nesimbi. Sezvo LME inopa zvibvumirano ane zuva expiry mazuva anosvika mwedzi mitatu kubva musi kutengeserana, vhiki zvibvumirano mwedzi mitanhatu, uye pamwedzi zvibvumirano kusvika mwedzi 123, rinobvumirawo kuti mari kutengeserana. Rinopa hedging, pose bhuku Pricing, uye kusarudza chaiko pakukurukura kugadzirisa zvibvumirano.  <response>: kutarisisa mitengo 