quick orbital question?

Question

So, correct me if I'm wrong, but P sub x, P sub y, P sub z goes from left to right and is like:  ___   ___   ___ 

M sub l values are -1, 0, 1, right? going in that order...

So why would the answer key say that when there is 1 electron occupying the p orbital (np^1) the m sub l value is 0?? Isn't it -1? 

I googled and couldn't find anything and forgot to ask teacher. 

Thanks! 

Update:

You could be right because that's what the answer key is saying..

But another source is saying 2p5 m sub l value is 0.. which makes sense to me..

I thought it went like:

 -1 0 1 

-2 -1 0 1 2 (d), so 3d^3 would have ml value of 0 for example..

Answer 1

M sub l values are -1, 0, 1,  >>  posible values, but NOT in that order ... the order if I remember is 0 .. +1 .. -1