Final answer:
The exact number of European countries assisted by the USA in 2017 is not provided, but it can be inferred that the U.S. contributed significant international aid to various countries, including EU members which were part of NATO.
Step-by-step explanation:
The question pertains to the number of European countries assisted by the USA in the year 2017. While the information provided does not directly state the exact number, it can be inferred through data reflecting international aid and the role of the United States as an aid donor. In 2010, for instance, the United States federal budget allocated $37.7 billion for economic aid, while private U.S. sources contributed an estimated 10 to $30 billion in the same capacity.
It is known that the U.S. is the largest contributor in absolute dollar terms, but in terms of the percent of gross national income, its contribution is relatively smaller compared to some other nations.Furthermore, in 2018, the European Union comprised 28 member states with a collective population of over 500 million.
The majority of these states are members of NATO as well, which includes the political alliance with the U.S. and Canada. Thus, it is likely that U.S. aide extended to various European countries through these memberships and international relationships. Specific data on U.S. aid to individual European countries in 2017 could be referenced from resources such as the United Nations Development Programme or related governmental documentation to provide a more precise answer.