1)
What is "Shiluchim"?
1.
Rashi: It is a dowry. Malbim - the verse explains how Shlomo was able to build Gezer; Kena'anim lived there. Pharaoh conquered it, burned it, and gave it to his daughter, and Shlomo built it.
2.
Radak: It is a gift. In place of gifts that one sends to his daughter, he gave this city.