根据对话情景的内容，从对话后所给的选项中选出能够填入每一空白处的最佳选项，并将答案填涂在答题卡上。选项中有两个为多余选项。
---Good evening. Grandma’s Restaurant. May I help you?
--- Good evening. 小题1:
---Thank you. May I have your name, Miss?
---Mary Brown.
--- 小题2:
---I’d like to order the “Free Matching Dinner for 2”.
---Yes, you may choose two soups, two drinks and four main courses from the menu.
--- 小题3:
---Are you ready? What Kind of soup do you want?
---Chicken soup and tomato soup.
--- 小题4:
---I’d like a plate of noodles, two chicken wings, some beef and a bowl of rice.
--- 小题5:
--- Just a coke and some green tea, please.
---May I have your address, please?
---Sure, 6A, Kingston Court, Belair Cardens, Shatin.
---Okay, your food will be delivered in half an hour. Thanks for calling.
A．May I book a table in your restaurant for tonight?
B．I would like to order some food for dinner.
C．Miss Brown, please tell me your order.
D．How about your main courses?E. Would you like some drinks?
F. Okay. Let me see.
G. And your drinks?
，其中ξ是服从区间(0，5)上均匀分布的随机变量，则此二次型为正定二次型的概率是______．