Find the size of each of the unknown angles. Help me plz​

Given the box plot, will the mean or the median provide a better description of the center? box plot with min at 10.5, q1 at 11.5, median at 12.5, q3 at 13.5, max at 15

If f(x)=2x-6 and g(x)=3x+9, find (f-g)(x)

When you find the area of a triangle do you use in. or in2