1)
There are always 12 Shevatim. Since Levi receives a portion, Efrayim and Menasheh should count as only one!
1.
Malbim: Indeed, they are considered like one 1 . It turns out that there are six Shevatim in the north, and six in the south, including Levi. The four heads of the Degalim ? Yehudah, Reuven, Efrayim and Dan, and to the right 2 of Terumas ha'Kodesh. Asher and Naftoli are by Dan; they were in his Degel. The other Shevatim are to the left (in the south).
