Which of the following statements are correct about the Mesopotamians?
1 . In geometry, the Mesopotamians had discovered what was later called the Pythagoras theorem .
2 . The Mesopotamians could calculate the length of the day and the night, and the rising and setting of the sun and the moon .
3 . They divided the whole day into 24 hours, a time system followed all over the world .
4 . They divided the sky into twelve parts and assigned each a name . This has come down to us as the twelve signs of the Zodiac or rashis as we call them in India .