American life changed dramatically during the first part of the nineteenth century. The United States' economy changed from a subsistence economy to a market economy. What does that mean and why did it happen? Write a well-constructed essay that: 1) Explains the difference between a subsistence economy and a market economy. 2) Explains the reasons why the shift to a market economy occurred. 3) Briefly describes the adjustments in manufacturing, agriculture, transportation, and communication that took place in each section of the country during this period. Which of these changes and Innovations helped unite the country and why? ( Please do not repost someone else's answer on brianly or from any other websites to answer my question). ( PLEASE ACTUALLY FOLLOW THE INSTRUCTIONS AND YOU'LL GET BRAINLIEST ☺ ).