How are lambs and tigers different

What is the meaning of the word checking as it is used in this sentence from the second paragraph of the passage?

How does it change your understanding of the laws to read them as a primary source rather than just a summary of laws?

Based on the cause-and-effect relationship in this sentence, what is the meaning of the word revert? the brownies kali made using a new recipe were too dry, so she reverted to her original recipe. a) to alter or change completely; revise b) to dispose of or remove; to throw away c) to prepare for something; assemble or make d) to go back to a previous state or practice