By 1840, how much cotton did the United States produce annually as a result of changes in technology?
a. about 3,000 bales
b. about 300,000 bales
c. about 1.3 million bales
d. about 1.3 billion bales.
By 1840 it was about "1.3 million bales" of cotton that the United States produced annually as a result of changes in technology, such as the cotton gin.
