Two major examples of how the Middle East and its Muslim nations influenced the economy of Western Europe are:
Fossil fuels
Sugar trade
The fossil fuels in the Middle East drove the energy requirements of Western Europe with relation to crude oil such that the Western Europeans sought to control the area by any means necessary.
The sugar trade was also influential because sugar was mostly controlled by Muslims and until the Europeans got to the New World, they had to rely on the Muslims of the Middle East for it.
In conclusion, sugar and oil from the Middle East were very influential on Western Europe's economy.
In the House, the majority party does all of the following except "A. select the minority party leader," since this task is left to the minority party unless something prevents them from doing so.