（Ⅰ）求a，b的值；

（Ⅱ）若对任意的t∈R，不等式f（t²﹣2t）+f（2t²﹣k）＜0恒成立，求k的取值范围．

    Today is the sixth of May. It is Nancy's birthday. She is eleven years old. There is a birthday party in the evening in her home. Many friends come. They all have a lot of fun at the party. Helen is listening to music. Yang Ling is playing the piano. Wang Bing and Mike are playing computer games. Now, it is time for the birthday cake. All the children sing “Happy Birthday” together for Nancy. Then, Nancy makes a wish, blows out the candles and cuts the cake. Everyone enjoys the party very much.

如图所示，小芳在做“探究影响滑动摩擦力大小因素”的实验时，操作的错误是____。纠正错误后，应拉动弹簧测力计使木块做____运动。若在木块上再放一个砝码，则木块运动时受到的滑动摩擦力将____(填“变大”“变小”或“不变”)。

二氧化碳由碳、氧两种元素组成，这两种元素的本质区别是（ ）

选择正确的翻译

街道（  ）