1. The document discusses time and space complexity analysis of algorithms. It analyzes three functions - abc(), Sum(), and RSum().
2. For abc(), the time complexity is O(1) as it performs a constant number of operations. For Sum(), the time complexity is O(n) as it iterates through an array of size n.
3. RSum() recursively sums an array. Its time and space complexity is O(3n) and O(n) respectively, as the depth of recursion is n and at each level it uses constant additional space.