Ask Mr Brain..all will be explained

How long is a nautical mile? A nautical mile is equivalent to 1,852 metres and is an international measurement used by planes and ships. It takes into account the curvature of the earth when travelling long distances. If you take the circumference of the earth at the Equator as a circle, you can divide the circle into 360 degrees. Each degree can be further divided into 60 minutes. The length of the arc of one minute is a nautical mile.

Is it true that a woman will get black circles around her eyes if she washes her hair during menstruation? No, it is not. It is perfectly safe for women to wash their hair during menstruation without fear of any adverse effects.

Superstitions about menstruation, such as that women should not wash their hair, take a bath or cook during menstruation, exist in many cultures but there are no scientific or medical explanations to justify them.

In some African cultures, menstruation was thought of as a symbol of fertility and a time when woman were endowed with magical powers. People were wary of upsetting menstruating women in case they cast a spell on them.

According to Jewish tradition, women are in a tameh (unclean) state during niddah (menstruation). Physical contact between husbands and wife is not allowed during this time. After niddah , the woman has to wait seven days then go to a mikva, a special pool to perform a purification ritual. Personal hygiene is important at all times and menstruation is no exception.

When did human beings first start to walk on two legs? The hominids, the immediate ancestors of Homo sapiens (humans), were notable for their bipedal locomotion, slow rate of maturation, their large brains, and among the more recent hominids, the development of language, tool use and social organisation.