要表示各班人数占全校总人数的百分比，你应选择（ ）统计图。
扇形
等距抽样的具体方法包括（）
A.随机起点等距抽样
B.半距起点等距抽样
C.循环等距抽样
D.随机起点对称等距抽样
E.半距起点对称等距抽样
A rescuer can most easily determine whether or not an adult victim has a pulse by checking the pulse at the（）.
A.carotid artery in the neck
B.femoral artery in the groin
C.brachial artery in the arm
D.radial artery in the wrist
