In some science fiction movies, evil robots refuse to die, no matter how hard people fight back.
     Now science fiction has become science fact. For the first time, scientists have made a robot that can take a beating(挨打) and keep on going. Scientists from Cornell University made the robot, which looks like a spider with four legs.
    Until now, even the most advanced(先进的) robot was almost certain to break down when it was damaged(毁坏). That is because its computer inside simply doesn't know how to make the machine work after its shape has changed.
    To deal with this problem, the scientists put eight motors(发动机) and two sensors(传感器) that read how the machine is working. They all give signals to the machine's software. Using this information, the computer can then figure out the machine's shape at any moment.
    The new technology is a big advance in robot-making, scientists say, and it's far from scary. It may someday help scientists create better artificial(假的) arms and legs and give new freedom to people who lose them. It might also help scientists understand how people and animals figure out their own sense of place in space.
   “It has been difficult to design robots that can work well when the environment changes or when it's damaged,” says Olaf Sporns of Indiana University in US. “With this work, we are nearer to solving this problem.”

为了探究“温度、湿度、光照”三种基因对鼠妇分布的影响，某生物兴趣小组进行了相关实验．请根据图1和图2回答有关问题．

①“x²+x﹣2＞0”是“x＞1”的充分不必要条件

②命题：“∀x∈R，sinx≤1”的否定是“∃x₀∈R，sinx₀＞1”．

③“若x= $\frac{\pi }{4}$ ，则tanx=1，”的逆命题为真命题；

④若f（x）是R上的奇函数，则f（log₃2）+f（log₂3）=0．