设$\overrightarrow{d_1}$与$\overrightarrow{d_2}$都是直线Ax+By+C=0（AB≠0）的方向向量，则下列关于$\overrightarrow{d_1}$与$\overrightarrow{d_2}$的叙述正确的是（　　）

在如图所示的电路中，电阻R₁=6Ω，R₂=8Ω，电源电压及定值电阻R的阻值未知，当开关S接位置1时，电流表的示数为0.4A，则此时R₁两端的电压是____ V；当开关S接位置2时，电流表的示数将大于____ A且小于0.4A．

    Most people have flown a kite or have seen one ride and dip(下降）in strong spring wind. Not so many people know that kites were first made in China thousands of years ago. The ancient Chinese were making and flying kites even before they were writing.

    A long time ago, the Chinese made kites to use in wars. They would fly these war kites in the dark. The kites were fixed(固定）so that they made strange sounds. Men at war would hear these sounds and run away. They thought those strange sounds were made by gods in the sky.

    The ancient Chinese also flew kites to bring good luck and to make their crops grow rich and tall. Sometimes they tied long strings(细绳）and hooks(钩) to their kites. Then they would fly the kites over water, letting the hooks hang down to catch fish.

    The Chinese use sticks(树枝), strings and paper for their kites. Some of these kites look like animals or trees. Others look like birds or houses.

关于我国的叙述，正确的是（　　）