By 1200, though water mills were plentiful in Europe, ____ provided the best source of power.
a. humans.
b. rotary oxen pulls.
c. small wood burning steam power devices.
d. water pumps.
e. windmills.
Question 2
Each solider in the Mongol army belonged to ____ units.
a. eleven
b. seven
c. two
d. ten
e. four