турист двигался 4 часа со скоростью 2.1 м/c а потом 5 часов со скоростью 1.8 м/с. чему равна средняя скорость туриста:?

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One day, when Arthur was a young man , Merlin and all the knights went to London . They met in a big church. When they came out, they saw something strange in front of the church . It was a very big stone with a large sword in it. The sun shone on the sword , and it looked very strong. On the stone were the words : "Only the king can take the sword from the stone . "

Every knight tried to pull the sword out of the stone. Nobody could do it – the sward did not come out. No one thought that Arthur was really the king. But he took the sword in his hand and pulled. It came out of the stone easily. Then the knights believed Arthur was a real king. Every body shouted, ‘Arthur is our king! Arthur is our king!’

Sir Ector , the king came to the tournament with his two sons , Sir Kay and the young Arthur . Arthur was sixteen years old . Young people want to fight with the other knights , but Sir Kay did not have a sword. Arthur was a kind young man . He wanted to help his brother . "There is a sword in the stone outside the church . I saw him on the way here ," he said . "I can go and get it for you. "

Arthur left Sir Kay and quickly went to church. Were not no more knights outside stone, because they were in the tournament. Arthur dismounted and went to the stone. He took the sword in his hand and pulled. He came from the stone easily. He ran back to his horse with a sword .

Then they went to the knights and told them everything . Knights were angry . They did not think that was really the King Arthur . So Merlin called all of them to the stone. Arthur put the sword back into the stone. Knights watched he pulled it easily. Then the knights believed. Everyone was shouting , " our King Arthur ! Arthur our king ! "