CREATE TABLE table_2656 ("Outcome" TEXT, "Year" FLOAT, "Championship" TEXT, "Surface" TEXT, "Partner" TEXT, "Opponents in the final" TEXT, "Score in the final" TEXT)

What is the surface made of if the opponent in the final is Hewitt McMillan?
SELECT "Surface" FROM table_2656 WHERE "Opponents in the final" = 'Hewitt McMillan'
SELECT "Surface" FROM "table_2656" WHERE "Opponents in the final" = 'Hewitt McMillan'