Hi,

please have a look at this:

http://community.wolfram.com/groups/-/m/t/458666

where it was made quite clear to me that we are not allowed to reply to homework questions. When I answered the question was not marked as homework. The links below show that we need to try to figure out what homework is; if we reply we appear to breach the community guidelines. In many cases it is difficult to be sure whether a post is about homework. I suppose that a conservative approach is in order then and one should refrain from replying.

This advice has changed my approach to replies here in the community substantially, but I fully understand that the Moderation team has to, well, moderate. Their place, their rules.

I do not think that a poster can delete your reply.

Best wishes,

Marco

PS: Please also refer to

http://community.wolfram.com/groups/-/m/t/464751

and

http://community.wolfram.com/groups/-/m/t/465051