How can i find the indepent variable in a question?

What is not true about kl and mn? what is mn? (show your work)

The sat and act tests use very different grading scales. the sat math scores follow a normal distribution with mean 518 and standard deviation of 118. the act math scores follow a normal distribution with mean 20.7 and standard deviation of 5. suppose regan scores a 754 on the math portion of the sat. how much would her sister veronica need to score on the math portion of the act to meet or beat regan's score?

What value of x is in the solution set of 4x - 12 s 16 + 8x? -10 -9 -8 -7