solution to both questions

[avishwak]

No description provided.

[super30admin]

The student has not provided any solution to the problem. Without seeing any code implementation, it's impossible to evaluate correctness, time complexity, space complexity, code quality, or efficiency.

To provide meaningful feedback, the student needs to submit their attempted solution. For a medium difficulty SQL problem, they should demonstrate understanding of:

1. Proper SQL query structure
2. Appropriate use of joins, subqueries, or window functions if needed
3. Correct filtering and aggregation techniques
4. Efficient query design