I expect there will be people who reply to this comment to argue it should be "E-T-C" or "Et Cetera". You can ignore those people; they probably say "exclamation mark" instead of "bang".
Not really a big difference in meaning or tone, if you ask me.
[1] Ha!
It is a school exercise at least in some European countries. It is a syntactic transformation of the sentence. Depending on the verb and other factors, the transformation preserves meaning, but sometimes it brings up a subject which was not clear in the original sentence in passive voice.
Thus, Numeromancer is suggesting a way for you to reflect on the scope of authority by using a syntactic transformation.