计算

我国自然灾害频繁，下列属于地质灾害的是（　　）

    Restaurant  owners  have to know how  ____  ( make) food. They also have to know how to make money. Here are some things they ____ (learn) from scientific studies. The color red ____ (make) people hungry. Red also makes customers____ (eat) fast food restaurants, therefore, have red furniture or walls. Soft colors like pink and light blue make people____  ( relax), so they spend more time____ (eat) their meals. Soft lighting____  ( make )people look good, but it makes food look bad. Loud music  makes people want____ (  leave). Hard seats also____ ( make ) customers want to eat quickly and leave. Many restaurants, especially fast food restaurants, use this knowledge ____ (make) customers eat faster.

有一列数：a₁、a₂、a₃、…a_n，从第二个数开始，每一个数都等于1与它前面那个数的倒数的差，若a₁=2，则a₂₀₀₇为（　　)