George Washington was the first president of the United States of America.
1830's-1840's is when The Adventures of Huckleberry was set
The Room of Requirement is located on Hogwarts' seventh floor, across from the tapestry of Barnabas the Barmy. To "open it" you must walk past the area of the door three times, thinking of what you need. For example: Say you need a place to study.
It basically means that you are doing something without knowing whats going to happen if you do that. (cause and effect)
