高白细胞血症时应预防的并发症为（）
A.高尿酸血症
B.电解质紊乱
C.酸中毒
D.凝血异常
E.碱中毒
参考答案：A, B, C, D
—Amy, I called you yesterday evening, but nobody answered the phone.
—Oh, I _______ a walk with my mother at that time. [ ]
A. take
B. took
C. am taking
D. was taking
△ABC的三个内角A、B、C的对边分别为a、b、c，已知sinB=1，向量(1，2). 若
，则∠C的大小为（）．
A.选项A
B.选项B
C.选项C
D.选项D
(1，2). 若
，则∠C的大小为（）．