Find the cosine of R. Write your answer in simplified, rationalized form. Do not round.

cos(R) =

Which set of reflections would carry trapezoid abcd onto itself? a) x-axis, y=x, y-axis, x-axis b) x-axis, y-axis, x-axis c) y=x, x-axis, x-axis d) y-axis, x-axis, y-axis, x-axis

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?

Two students were asked if they liked to read. is this a good example of a statistical question? why or why not? a yes, this is a good statistical question because a variety of answers are given. b yes, this is a good statistical question because there are not a variety of answers that could be given. c no, this is not a good statistical question because there are not a variety of answers that could be given. no, this is not a good statistical question because there are a variety of answers that could be given