They definitely buy scientific and graphing calculators. Your best bet is to call them and let them know the brand and model you have. The same goes for the DVD RW. It will depend on the brand / model, but they do buy them.
The writer, most likely. Not the calculator
The DVD writer would be something that look at for sure. The calculator on the other hand, depends on what you have. They only buy texas instrument ti-83, ti-84 and inspire.
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