SQUARE ROOT - [ R ]
SQUARED - [ S ]
PERCENTAGE - [ P ]
POSITIVE/NEGATIVE - [ N ]
FRACTION - [ F ]
CLEAR - [ C ]
CLEAR EVERYTHING - [ E ]
BACKSPACE - [ DELETE ]
DOT - [ . ]
ADD - [ + ]
SUBTRACT - [ - ]
MULTIPLY - [ X ]
DIVIDE - [ / ]
EQUALS - [ENTER]