The range of the following relation r {(3, −2), (1, 2), (−1, −4), (−1, 2)} is your a {−1, 1, 3} b {−1, −1, 1, 3} c {−4, −2, 2, 2} d {−4, −2, 2}

Acyclist bike x distance at 10 miles per hour .and returns over the same path at 8 miles per hour.what is the cyclist average rate for the round trip in miles per hour ?