1)
Why does it say "in Yerushalayim"? We know that he was king there!
1.
Malbim: This distinguishes between him and his father David, who also ruled 40 years, but David did not rule all 40 years in Yerushalayim and over all of Yisrael. Seven years were in Chevron, and only over Yehudah. All Shlomo's 40 years were in Yerushalayim and over all of Yisrael.
