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Do you know that……. What is a leap year? Each year is divided into twelve months, and each month into a certain number of days. Three years out of every four, a year has 365 days in it. In the fourth year, there are 366 days. This is a leap year. Every leap year an extra day is added to the month of February. Normally February has 28 days in it, but in a leap year it has 29 days. The purpose of this is to make up the difference between the calendar year and the solar year. It is convenient for us in daily life to go by a calendar year of 365 days. The solar year, which measures time by the Movement of the Earth round the Sun, is actually 365 days and about six hours long. In four years, these six hours a year make extra day, so we have a year with an extra day in it, a leap year.
Why does the wind blow? The wind is the air moving. We can also call this a breeze or a gale or many other names. Winds are caused by the surface of the Earth heating or cooling. Where warm air rises, the atmosphere pressure is high. Winds blow from high-pressure areas to low-pressure areas. Wind speed depends on how great is the difference in pressure between the cool and the warm areas. Land or sea breezes occur because land heats during the day more quickly than water, so warm air rises over land causing low pressure. Over the cooler sea, the air sinks, causing a high-pressure area. During the day, the sea breeze blows towards the land. At night, the land cools quicker than the water, so the pressure over the land is higher and the land breeze blows out to sea. Where do so many well-known wild animals come from? The African bush, a vast area of grassy, Shrub and tree-covered plains south of Sahara Desert is probably the home of more wild animals than any other. The lion, one of the world’s largest carnivores, or meat-eaters, lives there. So too does the largest animal to live on land, the African elephant. The giraffe, the world’s tallest animal, growing to a height of 5.5 meters, is found there also, along with a host of others, like the antelope, the jackal and the hyena, lions prey on the herds of antelope which find the bush an ideal home, with plenty of grass to eat and sufficient water to drink. Giraffes eat leaves and twigs from the tops of the acacia trees, and elephants eat tree branches which they pull down with their trunks, or roots which they dig up with their tusks.
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