Which of these is an example of a random sample? A.
Every twentieth caller to an independent radio station receives tickets to a concert.

B.
A phone survey is conducted using twenty names randomly taken from the phone book.

C.
Customers buying a new cell phone are surveyed about cell phone plans.

D.
A phone plan company surveys people on the beach to see how well they are receiving service, and uses this information in future advertising.

Lena reflected this figure across the x-axis. she writes the vertices of the image as a'(−2, 8), b'(−5, 6), c'(−8, 8), d'(−4, 2).

Set $r$ is a set of rectangles such that (1) only the grid points shown here are used as vertices, (2) all sides are vertical or horizontal and (3) no two rectangles in the set are congruent. if $r$ contains the maximum possible number of rectangles given these conditions, what fraction of the rectangles in set $r$ are squares? express your answer as a common fraction.

The two box p digram the two box plots show the data of the pitches thrown by two pitchers throughout the season. which statement is correct? check all that apply. pitcher 1 has a symmetric data set. pitcher 1 does not have a symmetric data set. pitcher 2 has a symmetric data set. pitcher 2 does not have a symmetric data set. pitcher 2 has the greater variation. ots represent the total number of touchdowns two quarterbacks threw in 10 seasons of play