1. The problem is to write the elements of Group 1, which are the first five natural numbers: 1, 2, 3, 4, 5. 2. Group 1 is simply the set \{1, 2, 3, 4, 5\}. 3. There is no further calculation or simplification needed as these are just the elements listed. Final answer: The elements of Group 1 are \{1, 2, 3, 4, 5\}.