1. 一种现代探测仪能探测肉眼看不到的东西,能用来探测地表中的金属,比如黄金。但是由于地表金属往往只有很小的颗粒,所以这个仪器也没什么大用。然而,还有有人拿他来探测黄金,因为———— 选项里一个说黄金所在的地表周围往往没什么东西 另一个说,找到一点黄金,他的地底下往往有大量的黄金1 2 GWD的 A certain cultivated herb is one of a group of closely related plants that thrive in soil with high concentrations of metals that are toxic to most other plants. Agronomists studying the herb have discovered that it produces large amounts of histidine, an amino acid that, in test-tube solutions, renders these metals chemically inert. Possibly, therefore, the herb’s high histidine production is what allows it to grow in metal-rich soils. a hypothesis that would gain support if ______. A: histidine is found in all parts of the plant – roots, stem, leaves, and flowers B: the herb’s high level of histidine production is found to be associated with an unusually low level of production of other amino acids C: others of the closely related group of plants are also found to produce histidine in large quantities D: cultivation of the herb in soil with high concentrations of the metals will, over an extended period, make the soil suitable for plants to which the metals are toxic E: the concentration of histidine in the growing herb declines as the plant approaches maturity.
希望考过的,没考过的NN谈谈应该选什么.谢谢!
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