Find all possible measures for ∡B if ∡A = 42°, a = 7 and b = 10

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.

Which expression is equivalent to sq-80

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