Another mistake with my code

Question

There an error at line 14 and I have no idea what it is because I’m new to coding
https://code.sololearn.com/WJ8PMSOr31Cb/?ref=app

Answer 1

You misspelled the btn variable on line 14

Answer 2

It's because your
btn is out of scope

U are declaring btn inside window.onload so u cannot use btn outside onload function , it's out of scope

Answer 3

I changed bnt to btn but now it says it can find variable bnt on line 14