CREATE TABLE table_73104 ("C_{low}" TEXT, "C_{high}" TEXT, "I_{low}" FLOAT, "I_{high}" FLOAT, "Category" TEXT)

How many different C_{high} values are there for the good category?
SELECT COUNT("C_{high}") FROM table_73104 WHERE "Category" = 'Good'
SELECT COUNT("C_{high}") FROM "table_73104" WHERE "Category" = 'Good'