题目

听下面一段较长对话，回答以下小题。【1】What will the woman do?A.See a doctor.B.Post some letters.C.Withdraw some money.【2】Where is the doctor's office?A.Near the bank.B.Near the post office.C.Near the supermarket.【3】What is the woman happy about?A.Going downtown.B.Finishing some tasks.C.Spending time with the man. 答案：【答案】【1】B【2】B【3】B【解析】【原文】W: I need to do some things around town today. Would you like to go with me?M: Sure. I don't have anything else to do today. What are we going to do? W: Well... I need to go to the bank and put some money into my bank account. Then I need to stop by the post office and mail some letters. Finally, I need to go shopping at the supermarket f抛物线y＝ax2＋bx＋3经过点A，B，C，已知A（－1，0），B（3，0）．（1）求抛物线的解析式；（2）如图1，P为线段BC上一点，过点P作y轴的平行线，交抛物线于点D，当△BDC的面积最大时，求点P的坐标；（3）如图2，在（2）的条件下，延长DP交x轴于点F，M（m，0）是x轴上一动点，N 是线段DF上一点，当△BDC的面积最大时，若∠MNC＝90°，请直接写出实数m的取值范围.