What circumstances might have induced the German emperor to pledge to "faithfully stand by" Austria-Hungary and its emperor?

On July 5th, 1914 Germany pledged faithfully to stand by Austria-Hungary, also called a Blank Check. This was a major event of WWI and a huge error by Germany. They pledged to back any action taken by Austria-Hungary regarding Serbia.

One consequence that might have induced Germany to give the blank check was that Emperor Franz Josef defended that the only way to balance power in the Balkans was to punish Serbia, which was pictured as a major threat to the Empire. Franz Josef also pictured Russia’s economic policy as a threat to the German Empire.

(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.

is there multiple