Help! I'm giving away all my points... i really wanna go to sleep
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1) 67.5 miles
2) 0.9(4)+0.9x+0.7x=13.50
3) 22
4) x+y+z=sums
5) Can't draw it. But do it in a graph. It is very easy just by plotting the points.
I hoped this help and I hope you do well on it!