Question

Identify valid and invalid variable names from the following:
percentage%, 12class, final-exam, Class,

Answer 1

Answer:

Variable name may not start with a digit or underscore, and may not end with an underscore. Double underscores are not permitted in variable name.

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The following are examples of invalid variable names:

age_ (ends with an underscore);

0st (starts with a digit);

food+nonfood (contains character “+” which is not permitted)