321. 1) 2) 3)

Solution:

The provided text consists of a number (321) followed by a numbered list with empty items (1), 2), 3)). This indicates the start of a problem or a question that requires multiple parts or steps to be answered.

To provide an answer, the actual questions for each numbered item are needed.

Answer: Please provide the specific questions for items 1, 2, and 3 under number 321.