Areliable source
(a) may contain some biased information.
(b) is written from a trustworthy point of view.
(c) is usually a secondary source.
(d) must be a primary source.

A reliable source can be primary or secondary, eliminating answers c and d. If it is truly reliable, then naturally it would not contain biased information, eliminating choice a. Therefore, the only feasible answer is b.

        i'm fairly sure that the correct answers are 2 and 3.

        i used both my knowledge of world history and the process of elimination to obtain these answers. option 1 cannot be a possible selection because the mandate of heaven belongs to ancient chinese philosophical belief. option 4 sounds like it would benefit the region than detriment it. however, both 2 and 3 explain a potential reason for what could have contributed to the fall of the roman empire.

      hope this ! if i were you, i'd get a second opinion, because i haven't taken this course for a year. best of luck!

***websites that me understand the curriculum better last year are and ***

there were 6 major base camps.   the base camps were located in alva, fort reno, fort sill, the madill provisional internment camp headquarters, mcalester and camp gruber.