已知函数f（x）=|x+2|﹣|2x﹣a|，（a∈R）．
（Ⅰ）当a=3时，解不等式f（x）＞0；
（Ⅱ）当x∈[0，+∞）时，f（x）＜3恒成立，求a的取值范围．
解：（Ⅰ）当a=3时，不等式f（x）＞0，即|x+2|﹣|2x﹣3|＞0，
∴ {x≤−2−x−
听独白，完成信息记录表。
How far is the school from Peter's home?
It's about kilometers.
How does Peter go to school?
He goes .
How many students are there?
There are students.
Where is the park?
It's the school.
What does Peter do in the park?
He plays with his friends.
Do you want to ________the story?
