please help

Question 21

What is variable scope and what does it mean to us as we write our code?

question 22

Write a function that takes in $total and $tax and returns the product of the two.

question 23

Write a msqli query that will use the connection object $conn and the string $find as the sql command, put the return into the variable $results.

Question 24

Write a JavaScript class called TheClass that contains a method called theAlert that pops up an alert saying "Boo"