Can someone let me know if this is correct? And if not what is wrong

Read the following passage. the early mill girls were of different ages. some were not over ten years old; a few were in middle life, but the majority were between the ages of sixteen and twenty-five. the very young girls were called "doffers." they "doffed," or took off, the full bobbins from the spinning frames, and replaced them with empty ones. based on the passage, early mill girls were mostly young. were mostly middle aged. were of a variety of ages. were mostly children.

When president johnson vetoed a law that would extend the freedmen’s bureau, congress reacted by supporting the veto and closing the freedmen’s bureau. writing a new law to show support for the black codes. overriding the veto and expanding the agency’s powers. drafting a law to prevent african americans from voting.

What is the difference between an independent and a dependent variable?