introducer of the math symbol e: crossword clues

Matching Answer
Confidence
ALG
60%
QED
60%
FCLEF
60%
IBM
60%
COLON
60%
GEOM
60%
THETA
60%
LCD
60%
SIGMA
60%
EULER
60%
e.g. Greek Cheese
e.g. O?D (Use ? for unknown letters)