What is a set? and examples of it.​

Which ratio is equivalent to 10: 85

The mean of a set of data is -3.82 and its standard deviation is 2.31. find the z score for a value of 3.99.

A, b, c, and d have the coordinates (-8, 1), (-2, 4), (-3, -1), and (-6, 5), respectively. which sentence about the points is true? a. a, b, c, and d lie on the same line. b. and are perpendicular lines. c. and are parallel lines. d. and are intersecting lines but are not perpendicular. e. and are parallel lines.