Which is the most direct effect that the internet has had on retail sales

The most direct effect that the internet has had on retail sales is THE DEVELOPMENT OF E-COMMERCE.
E- Commerce refers to the commercial transactions that are conducted via the internet. The advance in technology has makes it possible for the retailers to advertise their products and get across to the consumers via the internet. Buying and selling on the internet is now more preferable to most people than the traditional buying and selling because of its convenience.

In the midwest because it has more moderate climate than the north or south west which makes farming far easier.