from the top row, it takes on the last characters of the next entry, becoming "kgPa". Calculations involving i (the imaginary unit) with an exponent greater than 3 (e.g., i^4 or i^5) will result in a "DOMAIN Error", even when a solution exists. Usages The TI-36X series is one of the few calculators currently permitted for use on the Fundamentals of Engineering exam. While TI offers other calculators eligible for use on the exam, the TI-36X Pro is the most feature full Texas Instruments calculator permitted. HP and Casio also make calculators permitted on the exam. References External links Datamath.org, a museum of TI calculators Texas Instruments calculators