11.
Which function is used to read the entire content of a file into a string in PHP?
12.
How do you check if a file is writable in PHP?
13.
Which mode should be used to open a file for both reading and writing in PHP?
14.
What is the purpose of the 'x' mode when opening a file in PHP?
15.
Which function is used to write data to a file if the file doesn't exist in PHP?
16.
How do you get the file size in PHP?
17.
What does the 'rb' mode do when opening a file in PHP?
18.
How do you check if a file is readable in PHP?
19.
Which function is used to delete a file in PHP?
20.
What is the purpose of the 'w+' mode when opening a file in PHP?