Pleaseee check if this is correct

  The First World War was a worldwide conflict which began with the declaration of war by Austria-Hungary on Serbia on the 28th of July, 1914. The event leading to this was the assassination of Archduke Franz Ferdinand, the presumptive heir of the Austro-Hungarian Empire, by a Bosnian Serb.

Explanation:

credit card number 4 is the right answer

changes in factors like average income and preferences can cause an entire demand curve to shift right or left. this causes a higher or lower quantity to be demanded at a given price. demand curves relate the prices and quantities demanded assuming no other factors change. it is important for consumers to know this information, because it is crucial for them to know what they can afford and can't afford. i hope this .