Hippopotamus are huge.
Yes lol I remember reading in school about how even though they are so stocky they can run short distances
yes, they are 3rd largest mammals.
The book also talked about how their name comes from a greek word meaning 
Interesting. They are also not territorial on land.
I have heard they are pretty mean. it is so interesting considering they are closest relatives to dolphins and whales .
hippopotamus is among the most dangerous animals in the world as it is highly aggressive and unpredictable. 
They like to inhabit rivers and usually a male bull will have a few females around him. It you see one in the wild be extra carfull 
Despite its stocky shape and short legs, it is capable of running 30 km per hour.
interesting I think the only mammals bigger than them are elephants and rhinos