After a brief overview of the difference between perimeter and area, we'll discuss the various formulae needed for Q15-Q19.  Duration: 10:48

In addition to reviewing the formula for the circumference and area of a circle, we'll discuss a bit about π as well as the difference between rational and irrational numbers.  When it comes to writing down an irrational number, as you will see,  we have the option of writing our answer in either exact or approximate form.  Duration: 11:25

Here, I'll show you a simple investigation to remind you of the two essential properties of similar polyons.  Since one of those properties involves proportions, let's talk about those for a minute or two.  Duration: 7:44