A. (3,1,-1,+1/2) B. (3,1,1,-1/2) C. (3,1,0,-1/2) D. (3,0,0,+1/2)
A. (3,0,-1,+1/2) B. (3,1,-2,-1/2) C. (3,1, 2,-1/2) D. (3,0, 0,+1/2)
A. 0 B. 1 C. 2 D. 3
A. 对 B. 错