Instruct: Classify Amazon reviews into positive or negative sentiment
Query: The very best business calculator

Bought my first one of these in 1978, and they have only gotten better. I only replaced it because the keyboard has been used so much in 30 years that the case is looking a bit funky....mostly because of leaving it out uncovered in the tropical climate here in Hawaii. The capabilities are beyond my wildest expectations....and abilities. Mortage amortization is a snap, and I've even done discounted internal rates of return. If you don't know how to enter the problem the instructions will lead you through it. You can even set up multi-step programs to run your number crunching. The older ones used RPN which some find cumbersome 1-enter-1-+, but the new models can also use standard entry...1+1=2. Probably the last one I'll ever need to buy.