题目

已知抛物线y＝ax2＋bx＋c（a 0）经过点（1，0）和点（0，－3），且对称轴在y轴的左侧，则下列结论错误的是（ ） A . a＞0 B . a＋b＝3 C . 抛物线经过点（－1，0） D . 关于x的一元二次方程ax2＋bx＋c＝－1有两个不相等的实数根 答案：DIf someone says to you: “give me five”, do not search your pocket to get five yuan! It will make others laugh! The person's not asking for your money, but your fingers.　　In the US, "give me five" or "give me the high five" is a popular gesture (动作). You can see it often in films or on TV. It means the clapping (拍) of each other's raised right hands together.　　People do it when they meet for the first time or something happy happens. For example, a student has good marks in exams or wins a lottery ticket (彩票).If a football team wins a game, the players will give high fives to everyone around to celebrate.　　This gesture may come from the old Roman gesture of raising the right arm for the emperor to show respect. This also showed that the person raising his arm did not have a sword (刀) in his hand.　　Why not try to give the high five to your friends?根据短文内容选择最佳答案。（5分）【1】“Give me five” is a gesture to _______.A. make people laugh B. ask for moneyC. celebrate success D. give me five yuan【2】The gesture “give me five” is the clapping of _______.A. toes B. hands C. arms D. feet【3】When you ______, you give your friends high fives.A. lose your money B. go back homeC. win a football game D. pick up some money【4】The gesture started in _______ according to the story.A. Rome B. America C. China D. Britain【5】Why did the Romans raise the right arm for the emperor? Because ______.A. they were proud of their emperorB. they were happy to see the emperorC. they wanted to show their respect to the emperor.D. they wanted to show there were no swords in the emperor’s hands