Instruct: Classify the given review as either positive or negative.
Query: Batteries shouldn't be - This should be solar low energy.

So many calculators with solar power and a specially a book that you want to keep pick it up and start reading. You cannot have a battery run out.That is a flaw. I know the designers know about this..The size is also very condusive to have a solar light sensitive back or bottom panel. Why so many buttons? I have never seen a book with buttons..I know people could buy anything in this country, but this does not help the readers.. Make it basic simple give it a KISS..