今天留学360为考生带来了ACT科学测试题，希望考生能拿来认真练习，后面还有详细的例题分析，考生在做完题目之后可以认真的阅读下，看是否与自己的答题思路一致!
Passage 1
The following table represents the concentration of ions and dissolved gases in the sediment at the bottom of an ocean. A depth of 0 centimeters (cm) represents the top of the sediment. The concentrations are expressed in parts per million (ppm). The acidity of a solution is represented on a scale known as pH. A pH of 1 is very acidic, a pH of 7 is neutral, and a pH of 14 is very basic.
Table adapted from R.M. Atlas and R. Bartha, Microbial Ecology: Fundamentals and Applications. ？1981 by Addison-Wesley Publishing Company.
A certain type of bottom-dwelling microorganism thrives under the following environmental conditions: low concentrations of Fe2+, high concentrations of O2, and a neutral pH. Based on the table, at which of the following sediment depths would one most likely find this microorganism？
F. 0 cm
G. 5 cm
H. 10 cm
J. 15 cm
读题后第一个步骤就是找到题目问到的那个图表。这道题没有给出明确图表号，好在，这篇文章里也就只有一个表格而已。因此，我们就看这张表。
现在我们要找到这张表里哪部分是和答题相关的。我们要找的未知量是这些微生物的所在深度，已知量是“low concentrations of Fe2+, high concentrations of O2, and a neutral pH”。因此，我们应该将我们的视线转移到Fe2+ 及O2 的“Concentration in sediment”上以及pH值上，其它“concentrations”和“temperature”就不用看了。
这道题要“a low concentration of Fe2+(亚铁离子的一个低浓度)”，所以我们应该在表中圈出其最低的浓度，然后圈出O2 的最高浓度。最后，我们圈出最接近中性的pH值。我们可能不知道中性pH值是多少，那么我们就应该回到文章看，我们发现pH7是中性值。
根据标注，我们可以看到对应的深度值为0cm。然后我们再去看答案选项，最后找到选项F和我们预先得到的答案一样，最终答案便是它了。