分析测定出现以下情况，何种属于系统误差（）。
A、砝码读错
B、所用蒸馏水中含有干扰离子
C、试样未经充分摇匀
D、称取溶液时，有液滴丢失
参考答案：B
British "structuralism" linguists believed that elements in a language were ______, that is, lower level systems of word classes led to higher level systems of phrases and sentences.
A. classified B. rule-governedC. varied D. leveled
企业在产品销售过程中发生的运输费、包装费、保险费等计入销售费用。
