CREATE TABLE table_203_764 (id DECIMAL, "name" TEXT, "date" DECIMAL, "nation" TEXT, "displacement" TEXT, "speed" TEXT, "number" DECIMAL, "notes" TEXT)

what is the difference in speed for the gmt class and the te class ?
SELECT ABS((SELECT "speed" FROM table_203_764 WHERE "name" = 'gmt-class') - (SELECT "speed" FROM table_203_764 WHERE "name" = 'te-class'))
SELECT ABS((SELECT "speed" FROM "table_203_764" WHERE "name" = 'gmt-class') - (SELECT "speed" FROM "table_203_764" WHERE "name" = 'te-class'))