如图是一个制取氯气并以氯气为原料进行特定反应的装置．
已知A、B是圆O:x2+y2=1上的两个点，P是AB线段上的动点，当△AOB的面积最大时，则AO→·AP→-AP→2的最大值是（ ）
⑴The man is falling down the stairs.____
⑵The birds are flying away.____
⑶She is getting off the bus____
⑷My mum is on the phone.____
⑸They are having a birthday party.____
A. B. C. D. E.
________ Joe ________ Steve may go camping with you on Tuesday, because they are not allowed to go out on school days.
B. 
C. 
D. 
E. 
