Find the missing angle

What is the value of f(x) = 2.2 for f(-2)?

In the diagram, points d and e are marked by drawing arcs of equal size centered at b such that the arcs intersect ba and bc. then, intersecting arcs of equal size are drawn centered at points d and e. point p is located at the intersection of these arcs. based on this construction, m , and m

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25