甲、乙、丙都是短周期元素，其中甲、乙两元素原子的最外层电子数分别是次外层电子数的2倍和3倍，丙元素原子K层和M层电子数之和与L层的电子数相同。下列判断不正确的是[ ]
A．乙元素的族序数比甲元素的族序数大
B．甲、丙两元素最高价氧化物对应水化物的酸性强弱：甲＜丙
C．原子半径的大小：甲＞乙
D．含乙元素的化合物数目比含甲或丙元素的化合物数目多
答案：D
One day a wise man was walking along the beach when he saw a young man far away picking up something and very gently throwing it into the sea. As he got (31) he called out to the young man, “Good morning! What are you doing?” The young man (32), looked up and replied, “Throwing starfishes into the sea.” “Why are you throwing starfishes into the sea?” “The sun is up and the (33) is going away. And if I don’t throw them in they’ll (34).” “But, young man, don’t you (35) that there are miles and miles of beach and starfishes all along it. You can’t (36) make a difference!” The young man (37) politely. Then he picked another starfish and threw it into the sea, and said, “It made a difference for that (38).” There is something very (39) in each and every one of us. We have all been given the ability to make a difference to shape the future. We must each find our own starfish. And if we throw our starfish wisely and well, the (40) will be better.
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