题目

 -Would you like to come to dinner this Sunday, Xiao Ming? -________ A. I'd love to, but I have lots of things to do. B. Oh, no. That'll be too tired. C. I'll stay at home.              D. Yes, please. 答案：A　　在梯形ABCD中，AB∥CD，AD=BC，中位线EF=15cm，∠DAB=60，AC平分∠DAB，则梯形ABCD的周长为 (　) 　　A．30cm　　　　　　　　　　    B．40cm 　　C．50cm　　　　　　　　　　    D．60cm