混凝土用砂根据（）定出砂中含泥量、泥块含量。
A.混凝土量
B.混凝土强度等级
C.水泥标号
D.水泥用量
参考答案：B
The nurse is caring for a client in the first 4 weeks of pregnancy. The nurse should expect to collect which assessment findings
A．Presence of menses.
B．Uterine enlargement.
C．Breast sensitivity.
D．Fetal heart tones.
（）清理方法容易使钢发生氢脆。
A、火焰
B、风铲
C、酸洗
