Answer: (-0.5, 4)
Step-by-step explanation:
Midpoint formula: 
(x1, x2)=(2, -3)
(y1, y2)=(2, 6)
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Hope this helps!! :)
Please let me know if you have any question or need further explanation
Answer: -3 , 3
Step-by-step explanation:
thank me later;)
Yeah because he was at least 80% and when you add the grain and carbon that was total. Then divide the carbon. It will be 80%