你认为我国是否能实行西方的议会制度?为什么?

阅读短文，回答问题。

    Hello. I'm Peter. I'm a pupil. I go to school and study the boring knowledge(知识) every day now. I hope our school will change in the future. Schools will be different then. They will be under the sea, on high mountains and even in space. Robots will help us find books in the library and do our homework at home. We will use computers in all our lessons. They will help us see dinosaurs and other interesting things. We will have lessons with students from other countries. We will do a lot of things online together. We won't carry books to school. All our books will be on a small computer.

已知a-b=1，则代数式2b-2a-3的值是（   ）

如图，已知抛物线y=ax²+bx+c与x轴的一个交点为A（3，0），与y轴的交点为B（0，3），其顶点为C，对称轴为x=1．