An observer whose eye level is 2 meters is observing the top of an object with a mirror on the ground. The mirror is 3 meters from the observer and 6 meters from the object. Calculate the height of the object.

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

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?

Which letters from the table represent like terms? a and b b and c a and d b and d