题干
--How do you study for a test?
-- I study by asking the teacher help．
A：to
B：for
C：at
D：of
答案(点此获取答案解析）
B
--How do you study for a test?
-- I study by asking the teacher help．
A：to
B：for
C：at
D：of
的左、右两焦点，过F1且垂直于x轴的直线与双曲线交于A，B两点，若△ABF2是锐角三角形，则该双曲线的离心e的范围是 （ ）
