Determine which of the following are valid identifiers? If invalid explain why?

[TU,BSCCSIT,2066]

a. record1 => Valid

b. 1record => Invalid Identifier name must start with alphabets

c. file_3 => Valid

d. return => Invalid Keywords cannot be used as identifiers

e. #tax => Invalid Identifier should not contain any special symbols except underscore (_) symbol.

f. name => Valid

g. goto =>  Invalid It is a keyword and cannot be used as identifier.

h. name and address =>  Invalid No white spaces are permitted in name of identifier.

i. name-and-address =>  Invalid Identifier should not contain any special symbols except underscore (_) symbol.

j. 123-45-6789  =>  Invalid Identifier should not contain any special symbols except underscore (_) symbol. And also identifier name must start with alphabet.

k. void =>  Invalid It is a keyword and cannot be used as identifier.

l. name_address => Valid