CREATE TABLE table_203_201 (id DECIMAL, "class" TEXT, "type" TEXT, "ships" TEXT, "displacement" TEXT, "note" TEXT)

what is the difference in tonnes between the malabar class and the ut507 class ?
SELECT ABS((SELECT "displacement" FROM table_203_201 WHERE "class" = 'malabar class') - (SELECT "displacement" FROM table_203_201 WHERE "class" = 'ut507 class'))
SELECT ABS((SELECT "displacement" FROM "table_203_201" WHERE "class" = 'malabar class') - (SELECT "displacement" FROM "table_203_201" WHERE "class" = 'ut507 class'))