How did the operation of factories change with the invention of electric generators?
a.
they were able to operate 7 days a week.
c.
they were able to operate in the winter.
b.
they were able to operate in the summer.
d.
they were able to operate 24 hours.

its "d" they where able to operate 24 hours.

Which of the following best describes how oracle bones were used during the shang dynasty? a. oracle bones were used as a form of currency. b. oracle bones were used to make predictions about the future. c. oracle bones were used as artworks in private homes. d. oracle bones were used to mark the graves of family members.