One of the first things you notice upon entering apartment 5F is the beauty of its light. Each of the apartment's three large rooms also has an open view of Riverside Park and the Hudson River.    The eat-in kitchen is fitted with a Sub Zero refrigerator and top-of-the-line line stainless steel appliances, a through-the wall air conditioner,  plus two floor-to ceiling cabinets.  Of special note is  a uniquely designed space for a table and seating area with hidden storage.   The living room, foyers and kitchen have plank oak floors, which gives its classic beamed ceilings a contemporary feel while augmenting the living room's airy grace.   The bathroom has a glass enclosed shower, modern vanity and lights embedded in the ceiling.Easily accommodating a king size bed, the bedroom features a wall of six sliding door closets, plus additional hidden area with shelves for books, printer, and supplies.  ' 310 West 72nd Street is a full-service white glove building that offers full-time Doorman Service, Live-in Superintendent, Laundry, Bike Room, and Storage. Situated in one of the city's most coveted locales, this pet-friendly residence is just steps from Riverside Park with a dog-run park, playgrounds, and Pier I Cafe.  Trader Joe's, Citerella, Fairway are blocks away as is Central Park, Lincoln Center.  The one, two and three subways are a block away and the No. 57, 5 and West 72nd Street buses are around the corner.