Our understanding of the atom has changed over time. which idea that was once accepted is now considered scientifically inaccurate?
a. the nucleus is the center of the atom.
b. an atom is solid material.
c. electrons are arranged in layers.
d. electrons have a negative charge.

What does the country say concerning the status of free blacks living in the united states? a) they have the same rights as any other "free" people, and are full citizens. b) they have the same rights as any other "free" people, but are not properly citizens. c) they are citizens, but don't have the full rights granted to other citizens. d) they are not citizens, and have no right to petition the court.