CREATE TABLE table_20297668_1 (standard_yarn_weight_system VARCHAR2, wraps_per_inch__wpi_ VARCHAR2)

Name the standard yarn weight system for 9 wpi
SELECT standard_yarn_weight_system FROM table_20297668_1 WHERE wraps_per_inch__wpi_ = "9 wpi"
SELECT "standard_yarn_weight_system" FROM "table_20297668_1" WHERE "9 wpi" = "wraps_per_inch__wpi_"