CREATE TABLE table_38005 ("Unit" TEXT, "Russian" TEXT, "Ratio" TEXT, "Metric value" TEXT, "Avoirdupois value" TEXT)

What Avoirdupois value has a Russian of ?
SELECT "Avoirdupois value" FROM table_38005 WHERE "Russian" = 'берковец'
SELECT "Avoirdupois value" FROM "table_38005" WHERE "Russian" = 'берковец'