Angles are easy as pie

From the jacket flap: "You meet up with angles when you cut yourself a piece of pie, when you look for a good place to hide, and when you are hiking up a mountain - to mention just a few examples. **Angles are Easy as Pie** offers the opportunity to learn quite a lot more about angles: how to tell the difference between big ones and small ones, how airplane pilots use them, and how they figure in such shapes as tri*angles* and rect*angles*."