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Why do some trees lose their leaves in winter?

Some trees with broad-bladed leaves lose their leaves in the winter because the trees has a rest period during the cold weather, and the leaves are not needed for the production of food. These trees are called deciduous trees-from the Latin decidere which means to fall. They drop their leaves in temperate or cold climates, but remain evergreen in the …

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Norman Mailer

Norman Mailer — Norman Kingsley Mailer (January 31, 1923 – November 10, 2007) was an American novelist, journalist, essayist, playwright, filmmaker, actor and political activist. His first novel was The Naked and the Dead, published in 1948. His best work was widely considered to be The Executioner’s Song, which was published in 1979, and for which he won one of …

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Why do some people walk and talk in their sleep?

Our mind controls our actions and movement; yet while there are acts we are aware of doing, there are others performed without our knowledge. We breathe, walk, sit, stand and so on without really being aware of doing so, because these acts are so natural that we do not have to think about them. Sometimes it happens that some of …

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Why do some liquid burn?

Some liquids will burn because when their molecules mix with the oxygen in the air the mixture becomes combustible. The application of heat promotes the necessary chemical reaction to put the molecules into more violent motion, so that they collide at high speed. The jolt loosens the bonds and makes it easier for the molecules to rearrange themselves and escape …

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Why do some acids burn?

Some acids burn because they have a strong tendency to absorb water, giving out a great deal of heat in the process. Since most living cells contain water the strong acids, react with them and kill the cells, causing very serious burns. These three acids, as well as others such as perchloric acid and benzine sulphuric acid are called mineral …

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लपलौस का धमाका

Laploss ka dhamaka

मध्य प्रदेश के रायपुर जिले के आसपास का इलाका छत्तीसगढ़ कहलाता है। इस प्रदेश के कई दुसरे इलाकों की तरह यहाँ भी काफी संख्या में जनजातियां रहती थी। गाँव वाले और आदिवासी वैसे तो पड़ोसी ही होते थे लेकिन दोनों का रहन – सहन एक – दुसरे भिन्न होता है। गांव वाले तो ज्यादातर खेती – बाड़ी करके ही गुजारा करते …

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Why do soldiers wear khaki?

Soldiers wear khaki for camouflage, of course, to ensure that they blend with their background and make them less easily spotted by their enemies. In early times camouflage was not so important to soldiers; fighting at that time was usually hand to hand, and distinctive uniforms were necessary so that the combatants could discriminate between friend and foe. The uniforms …

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Why Do Plants Bear Fruit?

Do you like fruits? Have you ever wondered why plants produce fruits? Is it only because nature wants you to enjoy eating its fruits and sing its praises? The answer is no. Plants are much smarter than what you think they are. They actually use human beings, animals and birds who eat their fruits to propagate their kind. In other …

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