问题
填空题
已知圆锥的轴截面是等边三角形，则这个圆锥的侧面积与底面积的比为______．
答案
∵圆锥的轴截面是等边三角形，
∴圆锥的底面直径等于圆锥的母线长，
设圆锥的底面直径为2r，则母线长为2r，
∴圆锥的底面积为πr2，
侧面积为
×2πr×2r=2πr2，1 2
∴侧面积与底面积的比为：2：1，
故答案为：2：1．
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已知圆锥的轴截面是等边三角形，则这个圆锥的侧面积与底面积的比为______．
∵圆锥的轴截面是等边三角形，
∴圆锥的底面直径等于圆锥的母线长，
设圆锥的底面直径为2r，则母线长为2r，
∴圆锥的底面积为πr2，
侧面积为
×2πr×2r=2πr2，1 2
∴侧面积与底面积的比为：2：1，
故答案为：2：1．
One day a poor farmer was taking a bag of wheat to town. Suddenly the bag ___ from his horse onto the road. He did not know ____ to do about it because it was ____ heavy for him to lift by himself. He only hoped that someone would soon pass by and_____ him a hand. Just at this moment a man _____ a horse came up to him. But the farmer’s heart ____ when he saw who he was. It was the ___ man living nearby. The farmer had hoped to ask another farmer or a poor man like him to come along and help him. He couldn’t ask such a great man to help him. But to his ____ , the great man got off his horse as soon as he came nearer. He said to the farmer, “I see you_____ help, friend. How good it is that I’m here just at the right time.” Then he took one end of the bag, the farmer took the other end, they together raised it and put it on the horse. “Sir,” asked the farmer, “how can I pay you?” “It’s quite easy.” The great man replied with _____ .“Wherever you see anyone else in trouble, do the same for him.”
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