it depends. if you are writing in normal font, then one.
No, "River Flows in You" is not an original song in the Twilight series. It is a song composed by South Korean pianist Yiruma. It gained popularity independently of the Twilight series.
River flows in you - Yiruma
Song of Scarabaeus has 368 pages.
A Song for Summer has 288 pages.
Tailchaser's Song has 333 pages.
A Song of Stone has 280 pages.
Uhura's Song has 373 pages.
Regina's Song has 448 pages.
A Song of Sixpence has 344 pages.
Song of the Sparrow has 416 pages.
Alida's Song has 96 pages.
Dicey's Song has 196 pages.