Entrepreneurs contribute to a market economy by organizing productive resources in order to.. increase prices

prevent competition

create economic activity

hoard productive resources

create economic activity

Explanation:

Entrepreneurs come up with and implement business ideas by organizing some productive resources like land, labor and capital to enable them produce goods and services.

In so doing they are creating economic activity because the business will have to transact with other entities in order to remain viable. For instance, the business will have to employ people, buy goods from other companies and sell to others as well thereby creating business activity in the market.

(d) rivers.

explanation:

civilizations developed around rivers because their waters provided places to hunt and fish. also, as the rivers flooded, the lands around them became fertile. this allowed them to support farming. this is especially true of the nile river, which flooded the same time each year.

one of the negative side effects were the economic losses the events of september 11th caused. many, many people lost their jobs as a result of a downturn in the economy after the terrorist attacks.