Single-line comments, which are indicated by two slash (//) marks, and multiline comments, which are indicated by an asterisk and slash. Use (/*) to open a multiline comment and (*/) to close it.
Solution to Question 3-5
A semicolon (;) ends all statements in PHP.
Solution to Question 3-6
A value.
Solution to Question 3-7
By using the following form: $variable_name = value;
Solution to Question 3-8
Yes.
Solution to Question 3-9
They allow you to group code chunks together and execute them by their names.