定义一种运算“&”：“规定1&1=2，同时规定：若m&n=k，则m&（n+1）=k+2”，试计算：1&2005=______．

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