text: Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
  ### Context:
  CREATE TABLE table_12983929_1 (total_power VARCHAR, construction_start VARCHAR, commercial_operation VARCHAR)
  ### Question:
  How many different values of total power are there for the unit whose construction started on 01.03.1977 and whose commercial operation started on 01.02.1984?
  ### Answer:
  SELECT COUNT(total_power) FROM table_12983929_1 WHERE construction_start = "01.03.1977" AND commercial_operation = "01.02.1984"