【单选题】现金短缺成本与现金持有量之间成( )关系。
【简答题】碳素钢是指碳质量分数为______的铁碳合金。
【判断题】非合金钢(碳钢)是指以铁为基础、以碳为合金元素,碳的质量分数一般不超过 1.4% 的钢
【判断题】钢是指碳质量分数为ωc≥2.11%的铁碳合金。
【判断题】钢是指碳质量分数为ωc≥2.11%的铁碳合金。
【单选题】The studies mentioned in Paragraph 3 suggest that______.
A.
it is advisable for the old to read slowly
B.
out-of-place words are never negligible
C.
there is nothing that can distract young people
D.
old people may be more attentive in face of distractions
【单选题】非合金钢是指碳的质量分数为( )的铁碳合金,俗称碳素钢。