Pls help me for 30 points!

Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

Which graph represents the solution set for the given system of inequalities? x+2y< 3 x+y> 4 3x-2y> 4

Hi, can anyone show me how to do this problem? 100 points for this. in advance