Fix typos in the instructions

2/challenge-1/instructions.md

@@ -1,5 +1,5 @@
 # Challenge 1 - add the Code Scanning GitHub action to a repository
-In this challenge, we will enable code scanning on a fork of this repository and observe what vulenrabilities CodeQL finds. The repository contains several intentionally vulnerable code snippets.
+In this challenge, we will enable code scanning on a fork of this repository and observe what vulnerabilities CodeQL finds. The repository contains several intentionally vulnerable code snippets.
 
 If you prefer, you can choose another open source project, make a fork of it on your personal GitHub account and then enable Code Scanning on it. You can also choose one of your own public projects instead. If you encounter problems, see documentation for [enabling code scanning](https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/configuring-code-scanning-for-a-repository#configuring-code-scanning-automatically). 
 

2/challenge-4/instructions.md

@@ -20,7 +20,7 @@ from Call call
 where call.getLocation().getFile().getRelativePath().regexpMatch("2/challenge-1/.*")
 select call
 ```
-2. Hover over `Call` in the third line. This will show you the defnintion of the `Call` type. You can always hover over any part of the query to see if there is a defnition for it.
+2. Hover over `Call` in the third line. This will show you the definition of the `Call` type. You can always hover over any part of the query to see if there is a definition for it.
 3. Right click anywhere in the writing area of the query file and choose "CodeQL: Run Query on Selected Database"
 4. After a few seconds you should see results, like so: