I was planting a tree in my backyard and hit something hard. I dug it out and decided it was an ore of copper. I took its mass, and it was 65.0 grams. after some tricky experiments in my basement lab, I managed to extract 11.5 grams of copper. what is the mass percent of copper in the ore I discovered? a.63.5%b.18.1%c.5.65%d.17.7%