Mountains, highlands and rivers.
D is the answer i believe
Answer:Shipping low-yield crops great distances
Imagine a very large town in the center of a uniformly fertile plain; an isotropic space. Beyond the fertile space extends a desert that isolates the town from the rest of the world. There are no other populations. The only market buys all the agricultural production of the region, and is transported by the shortest route (a straight line).
In these conditions all men behave similarly in economic matters, that is, they have the same needs and abilities, produce equally and have a total knowledge of space and rationally conducts to achieve maximum performance, is the economic man. The differences in the cost of transport are taken into account depending on the distance, the quantity and the perishability of the merchandise.
Explanation:
pls mark brainliest
Calhoun argued that the US Constitution was based on a pact by 13 sovereign states.
Because they both had to cross a border to get here........you may have to be more specific on the question for me to answer it
