Dan 7:5

5 Behold, another animal, a second, like a bear; and it was raised up on one side, and three ribs were in its mouth between its teeth: and they said thus to it, Arise, devour much flesh.

a second, like a bear – this is the second kingdom on Nebuchadnezzar’s statue, which is Persia, represented by Cyrus the Great, who conquered Babylon. There was some kind of cooperation with the Medes. Cyrus, the Persian, conquered the Medes. Darius the Mede, initially was appointed as governor over Babylon. Therefore, Dan 8:20 called this kingdom: “the kings of the Media and Persia.” Isa 13:17 said the Medes would be sent against Babylon. Nonetheless, Cyrus the Great, was the “supreme ruler” of the kingdom.

three ribs in its mouth – this refers to Cyrus the Great, who conquered three kingdoms: the Median Empire (549 BC); the Lydian Empire (547 BC); and finally the Babylonian Empire (539 BC).