题干
After such a long way, he is .
A：walk; tired off
B：walks; tired out
C：walking; tired out
D：walking; tired away
答案(点此获取答案解析）
C
After such a long way, he is .
A：walk; tired off
B：walks; tired out
C：walking; tired out
D：walking; tired away
的中点，点P是直径MN上一动点，若⊙O的半径为1，则AP＋BP的最小值是