I am doing my first year of engineering and have EE as a compulsory course. My teacher recently gave this question in an exam. He gave me a 5/10. He is not answering anybody's doubts. Can anyone tell me what the right answer is/ where I have gone wrong. I have uploaded the evaluated answer sheets.

[![The question](https://i.stack.imgur.com/ED1va.png)](https://i.stack.imgur.com/ED1va.png)

[![My answers](https://i.stack.imgur.com/4g10Y.png)](https://i.stack.imgur.com/4g10Y.png)

[![My answers](https://i.stack.imgur.com/UTXVl.png)](https://i.stack.imgur.com/UTXVl.png)

[![My answers](https://i.stack.imgur.com/Vxhzd.png)](https://i.stack.imgur.com/Vxhzd.png)