1)
Why does it say "Kar'u Lahem Ken Halchu Mipneihem"?
1.
Rashi: All that the Nevi'im called to them, to teach to them the good path, they turned their necks away, to flee from the Nevi'im. It is the way of verses to speak like this, e.g. "k'Rubam Ken Chata'u Li" (4:7), "v'Cha'asher Ya'anu Oso Ken Yirbeh v'Chen Yifrotz" (Shemos 1:12).
2.
Radak: The Nevi'im called to them morning and evening, to repent to Hashem. Each time they called, Yisrael went away and did not heed their words, and did not cease their evil deeds.
2)
What is the significance of "la'Ba'alim Yezabechu..."?
1.
Malbim: The idols that they serve are the opposite - they call to them, and the Ba'alim distance themselves (do not answer)!