已知等差数列$\left\{a_n\right\}$的公差为2，若$a_1,a_3,a_4$成等比数列，则$a_2$=（   ）

（Ⅰ）求椭圆C的方程；

（Ⅱ）从椭圆C上一点M向圆x²+y²=1上引两条切线，切点分别为A、B，当直线AB分别与x轴、y轴交于P、Q两点时，求|PQ|的最小值．

未成年人依法进行自我保护，要求我们在面临险境时，要冷静、沉着、机智，要根据具体情况选择最佳方法，以保护生命为第一原则。（  ）

                                                                                        Everyone (人人)needs to be healthy.
   Do you eat healthy food every day? It’s important (重要)for your health. You need fruit, like oranges, apples and bananas. “ An apple a day can keep away（避开） the doctor (医生).” You also need vegetables, like carrots and broccoli. Fruit and vegetables are good for our health. But don’t eat lots of chocolate. It’s not good healthy food. What about dessert? Don’t eat lots of dessert because it’s not good for your health. Many people eat lots of chocolate and dessert, so they are unhealthy. Sports can also keep you healthy. Play sports every day. Don’t be lazy. You can be healthy.