Shortcoder deletes backspace in javascript

I coded this:

alert(“Your Score: ” + mark[n] + “\nSorry. You have to get 100% to go to the next lesson.\nPlease try again.\nThe page may take a few seconds to reload.”);

And when I reload the page, I get this:

alert(“Your Score: ” + mark[n] + “nSorry. You have to get 100% to go to the next lesson.nPlease try again.
nThe page may take a few seconds to reload.”);

The page I need help with: [log in to see the link]