Hi, I 'm Peter. This is the photo of my family. My grandfather is with glasses. He has little hair. The one standing next to him is my father. He is wearing a cap. My grandmother has gray hair. She is a kind woman. She is holding my younger sister. She has short curly hair. The woman standing behind me is my mom. She has straight( 笔直的 ) brown hair. There is a little boy sitting on the table. His name is Paul. He is my brother. He is wearing a green T-shirt and a pair of green socks. It's his favorite color. Which one is my uncle? Well, he is wearing glasses, too. He is in brown shorts and brown shoes. His name is Sam. Now, do you know where he is?

（Ⅰ）解不等式f（2x）+f（x+4）≥8；

（Ⅱ）若|a|＜1，|b|＜1，a≠0，求证： $\frac{f\left(ab\right)}{\left|a\right|}>f\left(\frac{b}{a}\right)$ ．