Results

There are some key words that you need to know for circles: radius, circumference, diameter, sector, segment, tangent, chord and arc. In this video you will discover what they all mean.

This video discusses the topic of circles.

This video explains the equation of a circle.

Video 1: Introduces the concepts of points, lines, rays and line segments
Video 2: Provides examples of points, lines, line segments and rays
Video 3: Common mistakes made

This 32 minute long YouTube video investigates the water contamination problems in Tanzania, with specific focus on Dar Es Salaam. 

This 11 minute long YouTube video describes the various causes and types of water pollutants.

This YouTube video investigates what water pollution is and some examples and effects of water pollution.