Based on the information in the excerpt, the inference that can be drawn about the effect the war between France and England had on the United States is:
The attacks on American shipping vessels led to a build-up of an American naval force.
This inference is supported by the mention of American shipping being vulnerable to French privateers and the subsequent response of arming merchantmen and warships to secure the sea lanes.
Regarding the effect of the War of 1812 on the U.S. economy, the correct answer is:
Manufacturing increased.
The War of 1812 stimulated domestic manufacturing as the U.S. sought to become less reliant on British imports due to blockades and the disruptions in trade.