A great intellectual and cultural development in Europe and the United States is the source of many discoveries, inventions and revolutions, for example: Declaration of Independence of the USA or French Revolution. It's also the time of philosophers - like Montesquieu, Voltaire, Jean-Jacques Rousseau, Diderot or d'Alembert - who all focus on the same subject: the questioning of political structures and traditional value systems such as religion, absolute monarchy, education, science etc.
There are two correct answers, 1 and 4.
Answer:
Please see the attached file, I have written the blog entry explaining what I think happened to the missing helicopter.
B calling makes sense in the sentence when applied to present tense