So I was going through some problems for a course that I am taking this semester and I came upon a problem that seemed to imply something. Let me first say that I am **not** looking for the solution to this problem, but rather it spawned a question that has me in the need for some clarification. 

The problem was to write a two-level logic version of the following equation using AND, OR, and NOT gates only. 

F = A + (B\*\$\bar C\$)

As far as I can tell - that's not possible unless the NOT gate does not count towards the depth. So this raised the question - does a NOT gate not count towards the depth of a circuit?

The definition I typically see is that the depth of a Boolean circuit is the largest number of gates between a given input and output. The textbook for my course also uses this definition. So is this the impossible task? Or am I just not thinking cleverly enough?

Thanks for any insight!