Generally, speed is a scalar quantity equal to the magnitude of velocity. Velocity is a vector quantity that is speed together with a specific direction.
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700a+1200r=1000000 (then plug in the a) 700(1000) +1200r=1000000 (simplify) 700000+1200r=1000000 (subtract 700000 from both sides) 1200r=300000 (divide by 1200 on both sides) r=250 250 pounds