Point A is the point of concurrency of the angle bisectors of DEF, what is the length of ZA

At store a, erasers are sold individually. the cost y of x erasers is represented by the equation y=0.75x. the costs of erasers at store b are shown in the graph.

If the alternate hypothesis of an experiment is “the true mean height of the giraffes is more than 15 feet” what is the null hypothesis?

Which is the value of this expression when p=3 and q=-9