Question

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Halloween
Halloween dates back to an ancient Celtic festival. The Celts, who lived
2,000 years ago in the area of Ireland, the United Kingdom and northern France,
celebrated their new year on November 1. This day showed that the summer was
over and winter had come. Because of the cold and darkness, winter was associated
with human death.
Celts believed that on Halloween night the ghosts of the dead returned to
earth. With their help, the Druids or Celtic priests, could predict the future. It was
important because people depended on the natural world which was dangerous and
changeable. They wanted to know what their life would be like in the next year.
For this event the Druids built big bonfires, where the people gathered to
burn crops and animals. It was a gift to the Celtic gods. During the celebration, the
Celts wore costumes made of animal heads and skins. They sang, danced and
listened to the stories the Druids told them.
In the second half of the nineteenth century, lots of immigrants started
coming to America. They helped to make the celebration of Halloween a popular
national event. Americans began to dress up in frightening costumes and go from
house to house asking for food or money. The most popular characters were
witches, ghosts, and vampires. Everyone tried to look as ugly and scary as
possible.
Halloween is closely associated with the Jack-o’-lantern, a pumpkin with a
candle inside that shines through the holes to make a horrible face. Most people
think that the Jack-o’-lantern is an American tradition. However, the original Jack-
o’-lantern was not a pumpkin but a man who, according to the old Irish legend
played a trick on the devil himself. He was punished for that and was accepted
neither to heaven nor to hell. The Irish people shared the legend with the
Americans and showed them how to make Jack-o’-lantern out of the pumpkin.
By the 1930s, Halloween had been celebrated with parades, town-wide
parties and lots of other entertainment. Later a new tendency appeared. By the
1950s, Halloween had changed into a holiday directed mainly at children. On that
evening children in costumes travel from house to house in order to ask for treats
(such as some sweets, a small present or a few coins) with the question “Trick or
treat?” The trick is a threat (usually not working) to perform mischief on the owner
of the house if no treat is given. “Trick or treat?” has become a traditional practice
on Halloween in many countries.
Who started Halloween?
Why was predicting the future important for the Celts?
What were the most popular characters in America?
What is the Jack-o’-lantern?
Who is the holiday mainly directed at ?

Answer 1

180 см2 = 0,018 м2;

4 см2 = 0,00004 м2;

Давление, оказываемое большим поршнем на малый равно давлению, оказываемому малым поршнем на масло. Принимая, что давление равно отношению действующей силы к площади поверхности, найдем силу, с которой малый поршень давит на масло:

F1 * S1 = F2 * S2;

F2 = F1 * S1 / S2 = 18000 * 0,018 / 0,00004 = 8100000 Н = 8100 кН.

ответ: F2 = 8100 кН.