He is not such a man _______ would leave his work half done.
A.that
B.which
C.who
D.as
答案:D
当x→0时,x-sinx是x3的()。
A.低阶无穷小
B.高阶无穷小
C.等价无穷小
D.同阶但非等价无穷小
学龄儿童早餐热量摄入应占全天热量摄入的()。
A.10%
B.20%
C.30%
D.40%
E.50%