Stanley drove his car on a business trip when he left the mileage was 840 miles in when he returned the mileage was 1200 miles the car was used 12 gallons of gasoline for this trip

The last answer choice

You need to do x2-x1,y2-y1 and divide it by 2 and you should get (1,-3) 

250 is the answeralright

The heir to the austrian throne, archduke franz ferdinand was gunned down by a young serbian terrorist. germany urged austria to declare war on serbia. russia mobilized against austria, then germany mobilized against russia. france and britain mobilized against germany. then young men such as adolf hitler volunteered in the war.