Please note that this is not a homework site. The purpose of homework is that you learn by doing. However, we are always willing to help solve problems you encountered, correct mistakes you made in your code and answer your questions.
We didn't see your attempts to solve this problem yourself and so we cannot correct mistakes you didn't made and answer questions you didn't ask. To get help you should do something yourself and get real problems with something. If your problem is "I don't understand a thing", then you should go back to basics and study again.
PC is the belief that changing the word but not the intent makes an insult 'clean enough to say in public' which is a moronic (IMHO) concept (can we still say moronic?). If you want to treat people with respect, lose the bad intent, and the words used stop being an issue immediately (for example certain races calling each other by a PC banned words is tolerated as no bad intent but cultural, proof of the moronic nature of the PC concept).
That said, its supposed to a professional forum, and posts should probably be on par with what is acceptable in the workplace. The solution there is the same... warn then ban/fire people that are constantly rude or you'll get a toxic forum/workplace. Again, all my opinion, which no one cares about anyway :)
You answered yourself. The title of the post can't have a mental handicap (nonsense as you said); so to make sense of it you have to continue to the common crude misusage (the word actually means slow: the title is slow?! that makes no sense either). Going down that path of translating it, the ONLY way to make sense of it is one of 2 ways... 1) the person posting is like someone with a mental handicap because they picked a pointless title for their post or 2) the post title is like what someone with a handicap would do. Both unraveled options are 'offensive' in today's professional (and hypersensitive) world's standards (agree or not, this is the world we live in). Both options disrespect both the OP and handicapped folks (by work-environment/pc standards).
There is no way that belongs here, if you follow it to those conclusions. I am not really a fan of PC, but I don't see anything good from saying thins like that here either.
1) the person posting is like someone with a mental handicap because they picked a pointless title for their post or 2) the post title is like what someone with a handicap would do.
Or 3) since colloquially "retarded" just means "really stupid" or "really dumb", and doing something dumb isn't exclusive to dumb people, when someone says "this is retarded", what they're actually saying is "the person who did this made a serious mistake when they did it".
If you actually believe that saying that something is "retarded" is implying that it's something a "retard" might do, then something you really shouldn't say in a professional environment is something like "this code is bad", because what you'd actually be doing is questioning the competence of your colleagues by implying that they're bad coders.
Taking offense is just a matter of trying hard enough.
In the past 5 minutes I've seen 2 posts titled "Question" and one titled "Help". Bad titles aren't helpful to those of us reading, but they certainly aren't uncommon, and they definitely aren't "retarded."
We should always remember that people come here looking for help, not insults. Be kind.