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_15318324_1 (r_z___arcsecond__ VARCHAR, r_y___arcsecond__ VARCHAR)
  ### Question:
  How many values of r z (arcsecond) correspond with a r y (arcsecond) value of −0.247?
  ### Answer:
  SELECT r_z___arcsecond__ FROM table_15318324_1 WHERE r_y___arcsecond__ = "−0.247"