CREATE TABLE table_79390 ("Model" TEXT, "Years" TEXT, "Engine code" TEXT, "Power" TEXT, "Torque" TEXT)

What is the torque of the xdrive20d model, which has a power of ps (kw; hp)@4000?
SELECT "Torque" FROM table_79390 WHERE "Power" = 'ps (kw; hp)@4000' AND "Model" = 'xdrive20d'
SELECT "Torque" FROM "table_79390" WHERE "Model" = 'xdrive20d' AND "Power" = 'ps (kw; hp)@4000'