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Ametalworker has a metal alloy that is 30? % copper and another alloy that is 55? % copper. how many kilograms of each alloy should the metalworker combine to create 90 kg of a 50? % copper? alloy?

Asalesperson set a goal to earn $2,500 in august. she receives a base salary of $1,000 per month as well as a 20% commission for all sales in that month. how many dollars of merchandise will she have to sell to meet her goal?

If f(x)= x^2 - 4 and g(x)=x^2 + 2 x, (b). (f-g)(x) i think i know the 1st 2 steps: f(x)-g(x) x^2-4 - x^2+2x