1) This code prints "Hello, world!" to the console using a macro from the included I/O library and then exits cleanly. 2) Hint 1: The `PRINT_STRING` macro handles the actual printing; your job is to ensure the string in the `.data` section is correctly formatted (null-terminated). Hint 2: The `xor eax, eax` instruction sets the return value to zero, indicating a successful exit to the operating system.