Keys And 2Nd Functions; The Display - Texas Instruments BA II PLUS User Manual

Keys and 2nd Functions

The primary function of each key is printed on the key. For
example, press $ to turn the calculator on or off.
Some keys provide a secondary function. which is printed in
yellow above the key. When you press &, the character,
abbreviation, or word printed above a key becomes active for
the next keystroke. For example, press & U to leave a
worksheet and return to standard-calculator mode.

The Display

The display shows entries and results with up to 10 digits. The
indicators along the top of the display provide information
about the status of the calculator and tell you what keys are
available at different times.
ABC represents the spaces where the three-letter abbreviations
for the variable labels are displayed.
4 BA II PLUS™ Calculator