He ordered barley because barley is used in producing beer and whisky and he wanted to drink alcohol because he liked it. He therefore changed one of the commandments from no animals shall drink to no animals shall drink to excess because it suits his needs. It's just one of the many commandments that he changed.
The Columbian Exchange lead to an increase in the demand for skilled labor in Europe, because D) an abundance of raw materials from the new world needed to be made into finished goods. Many raw materials and new products were brought over to Europe from the Americas which needed to be made into finished products.
