About a 100 years ago, when college classrooms were lit by fire and notes were ACTUALLY written on notebook paper, I used these graphic calculators in class. Each one takes 4 AAA batteries which I am afraid to ship. However, one has a watch like battery and I am not taking it out. Both work, the TI82 takes a bit to warm up but works perfectly, in fact, the last problem I worked on was saved and when i opened it, the problem appeared.
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