Can someone help me with history ?!

Why is it useful for historians to base certain studies on the analysis of historical themes

The map shows information about river valley civilizations. which feature of this map best the reader determine the distance between two places?

Which of the following statements about the fugitive slave act of 1850 is not accurate. a. marshals who refused to arrest a suspected fugitive could be fined $1,000. b. slave owners had to present evidence that an african american in the north was a fugitive slave. c. any person who provided food or shelter to a fugitive slave could be find $1000 and placed in jail for six months. d. it required all federal marshals to arrest any african-american suspected of being a runaway slave.