The railroad decreased transportation time across the united states from about six months to a. one week. b. three weeks. c. four weeks. d. five weeks.

americans had many intangible advantages. well since the british fought a war far from home military orders, troops, and supplies sometimes took months to reach their destinations, and the british had an extremely difficult objective. they had to persuade the americans to give up their claims of independence, americans had a grand cause: fighting for their rights, their independence and their liberty. this cause is much more just than waging a war to deny independence.

porter is writing economic history because he is focusing on the cost of developing vaccines.