The Hindu-Arabic numerals were invented by mathematicians in India. Perso-Arabicmathematicians called them "Hindu numerals" (where "Hindu" meant Indian). Later they came to be called "Arabic numerals" in Europe, because they were introduced to the West by Arab merchants.
Federalism creates the separation of powers between the three branches of government
A case serving as precedential means that Judges in later cases use that case as the bench mark for how to rule on a particular issue.
So, Marbury v. Madison stands for notion that the Judiciary can review the actions of the legislative and executive branch to determine constitutionality. Later courts would cite Marbury v. Madison as precedent in cases that involved judicial review of legislative action.
France entered World War I on August 3, 1914, when Germany declared war. France played only a small part in the diplomatic crisis of July 1914–its top leaders were out of the country from July 15 to July 29, when most of the critical decisions were taken. Germany entered into World War I on August 1, 1914, when it declared war on Russia. In accordance with its war plan, it ignored Russia and moved first against France–declaring war on August 3 and sending its main armies through Belgium to attack Paris from the north.