Will I be allowed to use a screwdriver during the exam to replace the batteries in my calculator?
Yes. You may bring one and keep it in your pocket or place it under your chair.
Why are only two calculator models allowed for use during the exam?
Many calculators have text-storing capabilities which could create an unfair advantage and compromise the integrity of the exam. It is a standard practice of many professional testing organizations to provide a short list of permissible models. In the current policy, the HP model is available for candidates who prefer Postfix notation entry, and the TI model is available for those who prefer algebraic notation entry.