Which of the following statements accurately describes the contribution of eratosthenes?

a: he is considered to be the "father of history."
b: he believed that all diseases have natural causes.
c: he wrote comedies such as "the clouds" and "the birds" to be performed in a large outdoor theaters.
d: he estimated the earth's circumference.

he sent troops to protect the students as they entered the school.

1. it was caused by feudalism

2. charlemagne used christianity as a major cornerstone for his rule. cloisters were built all over the empire to act as centers for the (re)population of the vast european wilderness.

3. the europeans feared the next raid every time chetak

i'm not so sure about #6. but i hope i you with the first 3.