In calendar-mode to invoke d on a specified day, it will prompt the activitiesof the day from file ~/diary.
Is it possible to invoke an agenda view of a particular day from calendar?
Sure, just press c (which is bound to org-calendar-goto-agenda) while the cursor is at the date you wish to have a look.
Not a direct answer to your question (@aadcg's answer does that perfectly), but in Emacs you can "look around" and see what keys are bound to what functions in any particular situation (that's part of the "self-documenting" part of the description of Emacs): in this case, while you are in the calendar, say C-h m: you'll get all the key bindings available, listed in a separate buffer (which means you can also switch to that buffer and do an interactive search for org to find all the keybindings that might have something to do with Org mode).
