What is the difference between abstract and concrete noun

Which of the following would be an open question? a.did you get along with your last boss? 2.what kind of hobbies do you have? 3.when could you start working for us? 4.what was your g.p.a. in college?

Is an example of a nation that uses a democratic republic type of government.

Atopic list should contain a. main topics covered in class c. important vocabulary words b. main ideas from the text book d. all of these