Many achievements made during the golden ages of both islam and the west african kingdoms reached european societies by way of

1.

trade networks in the mediterranean sea region
2.

trade expeditions between china and africa
3.

the voyages of ferdinand magellan
4.

the travels of commodore matthew perry

what do you                                                                                                                                              

when a country suffers, for example, a drought period, the market product is affected for a low offer, in this case, potatoes; the government has to tax to the households, which have to give more money for the potatoes which they consume, that situation make them consume substitute goods even through loans, it could increase the financial market movement and the inflationary phenomena, the business has to increase salaries in order to the employees could buy a more expensive food (potatoes) and in order to inflation tha business had to buy expensive supplies in the factor market, while the rest of the world have to gain more money to consume the same amount of potatoes.