Which of the following best explains why cosine 2π/3 ≠ cosine 5π/3?

The standard deviation for a set of data is 5.5. the mean is 265. what is the margin of error?

What sums are equal to 6/12? choose all answers that are correct a.6/12+6/12+6/12+6/12+6/12+6/12 b.2/12+1/12+1/12+2/12 c.5/12+1/12 d.1/12+1/12+1/12+3/12 plz : )

3x = 729 solve for x plz . it's urgent. will mark