Which symbol is used in standard sql as a wildcard to represent a series of one or more unspecified characters? % (percent sign) ; (semi-colon) _ (underscore) ! (exclamation mark) ? (question mark)

% (percent sign)

Explanation:

% (percent sign) in SQL is used to represent any number of unspecified characters. For example, Ex% will match Example, Expensive, Exclaim, etc

you can not change you age soon as you signed up. the only way is too delete your account and use another account to sign up and put your correct age.