There are about 0.62 miles in a kilometer.    A more exact answer:   One mile is 5,280 feet. One foot is 0.3048 meters. Therefore one  mile is 1,609.344 meters, orâ¦ 1.609344 km. Dividing 1 km by that  figure gives the answer that one km is 0.6213711 mile.
The jejunum (/dÊáµ»ËdÊuËnÉm/) is the second part of the small intestine in humans and most higher vertebrates, including mammals, reptiles, and birds. The jejunum lies between the duodenum and the ileum. The jejunum is considered to begin at the attachment of the suspensory muscle of the duodenum to the duodenum, a location called the duodenojejunal flexure. The division between the jejunum and ileum is not anatomically distinct.
That answer can never be accurate because it all depends on the size of the rat, but it can an average. The duodenum is 8 cm, Jejunum is 80 cm, Ileum is 3 cm and Large intestine is 16 cm. And here is a site with a short answer to why the small intestine is longer than the large intestine. I'm no rat scientist :) but I got this out of my biology book and some research, so I hope this works :)