The cone and cylinder below have equal surface area

What is the period of the sinusoidal function ?

Kaley cuts half of a loaf of bread into 4 equal parts. what fraction of the whole loaf does each of the 4 parts represent?

Right triangle abc and its image, triangle a'b'c' are shown below. algebraically prove that a clockwise and counterclockwise rotation of 180o about the origin for triangle abc are equivalent rotations.