A: Yes you can, but UPS may not leave the cake if no one answers the door. Also, if the apartment is in a residential community, UPS may deliver your cake to a mailroom/front desk/office.
With sending king cakes to someone who lives in a dorm, be certain that all important information: name of the dorm, street address of the dorm, suite/apartment number or alphabet of the dorm are listed. i.e. Louisiana Dormitory, 123-4 Whatever Street, Dorm 4C, City, State and Zip Code.