右心室肥厚时,心电图V1导联出现q波可能是由于()。
A.隔侧 * * 肌肥大
B.隔缘肉柱增生
C.室上嵴肥厚
D.右心室游离壁增厚
E.梳状肌增生
参考答案:C
已知a,b是一元二次方程x2+4x-3=0的两个实数根,则a2-ab+4a的值是______.
He's got himself into a dangerous situation ____ he is likely to lose control over the plane. [ ]
A. where
B. which
C. what
D. why