题干
——Whose book is this ?
——It _____ Tom's . There is his name on it .
A：can't be
B：must be
C：can be
答案(点此获取答案解析）
B
——Whose book is this ?
——It _____ Tom's . There is his name on it .
A：can't be
B：must be
C：can be
的圆心角与圆弧围成的扇形面积为（ ）
