Sombody help me please

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.

If f(x)= sqrt4x+9+2, which inequality can be used to find the domain of f(x)?

Write the pair of fractions as a pair of fractions with a common denominator