CREATE TABLE table_43214 ("Rank" FLOAT, "Name" TEXT, "Span metres" FLOAT, "Span feet" FLOAT, "Material" TEXT, "Year opened" TEXT, "Country" TEXT)

Which country's material was concrete when the span metres were less than 270, span feet is more than 837, and the year opened was 1943?
SELECT "Country" FROM table_43214 WHERE "Material" = 'concrete' AND "Span metres" < '270' AND "Span feet" > '837' AND "Year opened" = '1943'
SELECT "Country" FROM "table_43214" WHERE "Material" = 'concrete' AND "Span feet" > '837' AND "Span metres" < '270' AND "Year opened" = '1943'