题目

How quickly can you count from one to ten? Do you use ten different words to do it? Can you do it in English, or do you have to use your first languages? Do you count on your fingers? Many people think that numbers and math are the same all over the world. But scientists have discovered that it is not true. People in different parts of the world use different ways to count on their fingers. In the United States, people think begin counting with their first fingers, which they extend or stick out. They then extend the rest of their fingers and finally the thumb(拇指）to count to five.18．含有砒霜（As2O3）的试样和锌、盐酸混合反应，生成的砷化氢（AsH3）在热玻璃管中完全分解成单质砷和氢气．若砷的质量为1.50mg，则下列说法正确的是（　　）A．被氧化的砒霜为1.98mgB．分解产生的氢气为0.672mlC．转移的电子总数为0.18NAD．和砒霜反应的锌为3.90mg