Which medium (or media) do you think would be appropriate for each of the following kinds of

Question:

Which medium (or media) do you think would be appropriate for each of the following kinds of messages a subordinate could receive from his or her boss:
(a) A raise.
(b) Not receiving a promotion.
(c) An error in a report prepared by a subordinate.
(d) Additional job responsibilities.
(e) The schedule for company holidays for the upcoming year? Explain your choices.