1)
Why is it called "Rochav"?
1.
Malbim: Since from north to south it was also 100, and that is called length, we can call from north to south 'width'.
2)
How was it 100 with "veha'Gizrah la'Kadim"?
1.
Rashi: Now it includes 15 Amos for Beis ha'Chalifos in the north, and 15 in the south.
QUESTIONS ON RASHI
3)
Rashi writes that "Gizrah" is the Bayis. Why does it say "ha'Bayis veha'Gizrah"?
1.
Radak: Rather, the Bayis is the Heichal; "Gizrah" is the Aliyah.