Is the following relation a function? Relation:
{(2, 1), (-4, 5), (1, 7), (2,-3)}

Domain:
{ -4, 1, 2}

Range:
{-3, 1, 5, 7}

The physical fitness of an athlete is often measured by how much oxygen the athlete takes in (which is recorded in milliliters per kilogram, ml/kg). the mean maximum oxygen uptake for elite athletes has been found to be 60 with a standard deviation of 7.2. assume that the distribution is approximately normal.

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning

10x − 5y + 14 = 0 whats the answer pls