Why is it not recommended to make all of a class's variables public?

You want to use wildcard characters when searching for records in a MySQL/MariaDB database using a PDO prepared statement. Which code should you use?

Assume that $r is 255, and $g and $b are both 0. What is the correct code to output "#ff0000"?

You want to find out what day Twelfth Night falls on after Christmas 2018. Which code should you use?

Which loop displays all numbers from 1 to 10 inclusive?

Which are types of control structures in PHP?

How can you call this function? $greet = function($name) { printf('Hello %s\r\n', $name); };

The PHP function which capitalizes the first letter of each word in a string

Which statement opens a file for writing, to append data at the end of its content ?

What's the output? $values = array(0, NULL, FALSE); foreach($values as $key => $value) { echo isset($values[$key]) ? 'TRUE ' : 'FALSE '; }

What is the recommendation regarding PHP closing tags in a document?