单项选择题
A.(10,50,80,30,60,20,15,18) B.(10,18,15,20,50,80,30,60) C.(10,15,18,50,80,30,60,20) D.(10,30,60,20,15,18,50,80)
A.10 B.11 C.21 D.36
A.1和1 B.1和2 C.1和3 D.2和2