Knowledge

What causes an "ice cream headache"? What causes headaches? Why do we perspire? Why do we laugh? How much sleep do we need? What are teeth made of? How much of the Sahara Desert is covered by sand? What's the highest magnetic field ever measured? What was the first prepaid, adhesive postage stamp? What is a black hole? Why does an "X" mark stand for a kiss? What insect guides its flight with special movement sensors? What creatures have four kinds of legs? Where do fungi fit in the tree of life? Do you know the tomato is the world's most popular fruit Do you know how our fingernails grow? Why do we laugh? Why do the stars twinkle? How did the custom of kissing start? How come we have two eyes but only see one of everything? Why do Onions make us cry? Why don't women have beards? Why is some hair curly and some hair straight? Why is your middle finger the longest finger? Why is a wedding ring always worn on the third finger? Why do people say that cats have nine lives? Why do we blink our eyes? How come tears come out of our eyes when we cry? What would happen if there were no dust? What makes people sneeze? What makes popping corn pop? What is the "baby boom"? Why are some people left handed? How the vacuum cleaner was invented ? Why do we get Goose Bumps when it is cold? How much sleep do we need? Why do we get a shock from electricity? What happens to bees in winter? Why is milk white? How is chocolate made? Why can caffeine keep people awake? Why do we perspire? What do these three letters stand for? How did the custom of kissing start? Can dogs see colors? Why do we get hiccups? They Are Good-for-Your-Body Foods Why do bulls charge when they "see red"? What causes headaches? What causes an "ice cream headache"?

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