True. The United States and Great Britain practiced Isolationism.
The "Scramble for Africa" had its roots in European politics.
The Congress shall have Power ... To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof.
b.) Denied powers
The development of farming was crucial to the formation of civilization since this allowed for there to be a surplus of food, which meant that people could devote themselves to other tasks and skills that are necessary for society to form.