Answer: regressing
Explanation: if a person degenerates, they are losing capabilities and their qualities are decreasing or declining. Basically things are getting worse.
Regressing is returning to an older, less developed state while progressing is getting better.
Degenerating and regressing are going backward while progressing is going forward.
Working out: 6.25% = 4 half lives (20x4=80ma) 80ma is how old the rock is
It's the last one. we know this because it talks about how even with the smart hands of a scientist, the plan is not completely foolproof, or safe
<span>it's D: All astronauts had master’s or doctorate degrees, but only two were jet pilots; consequently, the astronauts with no flight experience had to complete one year of flight training.
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