题目

补全对话A: Do youEnglish?B: No, IA:your favorite subject?B:favorite subject is PE.A:do you like it?B: Becauseexciting.A:your P.E.teacher?B: Mr. Liu.A: Isyoung?B: Yes. He's only twenty-three years.A: Is he strict (严格)?B: Yes, but we all like 答案：【1】like【2】don't【3】What's【4】My【5】Why【6】it's【7】Who's【8】he【9】old【10】him（坐标系与参数方程选做题）在极坐标系中，直线的方程是，以极点为原点，以极轴为轴的正半轴建立直角坐标系，在直角坐标系中，直线的方程是.如果直线与垂直，则常数         .