静止流体内各点的压强都相同。

下列词语中没有错别字的一组是[ ]

A．噩梦 迟顿 人事纠纷 豁然开朗

B．脚趾 磕睡 扭转乾坤 安分守己

C．老茧 宽敞 翻箱到柜 逆来顺受

D．黯然 汽艇 金碧辉煌 三差两错

既能活血祛瘀，又能利尿消肿的药物是（）。

A.益母草

B.茜草

C.通草

D.车前草

E.白茅根

数据分析的目的之一是确定质量管理体系的适宜性、充分性、有效性。（）

既想参赛锻炼自己，又怕成绩不好被人讥笑，此时的动机冲突是

A．双趋冲突
B．双避冲突
C．趋避冲突
D．双重趋避冲突
E．双重避趋冲突

Most plants can make their own food from sunlight, (1) some have discovered that stealing is an easier way to live. Thousands of plant species get by (2) photosynthesizing, and over 400 of these species seem to live by pilfering sugars from an underground (3) of fungi(真菌). But in (4) a handful of these plants has this modus operandi been traced to a relatively obscure fungus. To find out how (5) are (6) , mycologist Martin Bidartondo of the University of California at Berkeley and his team looked in their roots. What they found were (7) of a common type of fungus, so (8) that it is found in nearly 70 percent of all plants. The presence of this common fungus in these plants not only (9) at how they survive, says Bidartondo, but also suggests that many ordinary plants might prosper from a little looting, too.

Plants have (10) relations to get what they need to survive. Normal, (11) plants can make their own carbohydrates through photosynthesis, but they still need minerals. Most plants have (12) a symbiotic relationship with a (13) network of what are called my corrhizal fungi, which lies beneath the forest (14) . The fungi help green plants absorb minerals through their roots, and (15) , the plants normally (16) the fungi with sugars, or carbon with a number of plants sharing the same fungal web, it was perhaps (17) that a few cheaters—dubbed epiparasites—would evolve to beat the system. (18) , these plants reversed the flow of carbon, (19) it into their roots from the fungi (20) releasing it as "payment.\

18（）

A. in time

B. overtime

C. at times

D. behind time