What did the Egyptians invent that helped keep track of when the Nile would flood?

I'm pretty sure it was a calendar because the Nile would flood around the same time each year

Hope this helps!!

Explanation:

well, i can't read it so i'll ask you questions about it : )

if you were a reader and you read the introduction, would you want to read more?

does it start with a question? if so, is it something you would want to read about?

and ask any friends or family for their opinion : )