1)
Why does it mention specifically Chatas Yaravam?
1.
Malbim: Avodas ha'Ba'al ceased in the days of Yehu, but Yaravam's calves remained until the end of Malchus [Yisrael] 1 . They tore away from Beis David, and they could not ascend to Yerushalayim, where Malchei Beis David were.
1
Rashi (17:2, from Seder Olam 22) said that the calves were removed during the first two exiles. This was shortly before the end of Malchus Yisrael. (PF)
