Why is an allow$-$list usually better than a deny$-$list when doing input validation?

Come up with an example where a deny$-$list might serve a particular environment better than an

allow$-$list and be specific if you can.

$7)[5$ points$]$ Suppose you were asked to test some code for possible issues handling exceptions.

Describe briefly how you would go about testing to see if your code was exception$-$safe.

$8)[6$ points$]$ You are tasked with taking raw input data from a user, creating a string with it and

then doing a system$()$ call with that string in C$.$ Describe how you might go about ensuring that

this operation is safe for your system.