Test your knowledge of some common and unusual phobias with these multiple choice questions...

How our bodies work is so often a source of fascination and bewilderment. Test your knowledge of the human body with these multiple choice questions...

Various scales and charts have been developed to measure everything from the pungency of peppers to the intensity of earthquakes. Test your knowledge of some of them with these multiple choice questions...

Helicopter enthusiasts will tell you that rotorcraft are not only cooler than their fixed wing counterparts, but safer too! Test your knowledge of some of the world’s most famous models with these helicopter multiple choice questions...