Let us have something iced to drink?答案：A
Let's have something iced to drink?答案：B
A:will you B :Shall we
Let's 开头的祈使句,后用shall we（或用shan't we)
Let us 开头的祈使句,后用will you（或won't you）?
Let's go and listen to the music,shall we（或用shan't we)?Let us wait for you in the reading-room,will you （或won't you）?