R. Shimon b. Yochai says: Where a plain yields a kor, a mountain yields five korim; a kor in the north, a kor in the south, a kor in the east, a kor in the west, and a kor on top — five times the yield (of a plain). Similarly, (Ezekiel 5:5) "This is Jerusalem. Among the nations have I placed her, and all around her are lands." And elsewhere, it itself is called a land. How are the verses to be reconciled? It is a land which contains many different kinds of land — fruitful land, sandy land, dusty (non-fruitful) land.