The first three. Multiple escapes, a safe meeting place, and practice
Bacteria lives on the outside of foods, especially raw meats. When you cook a steak, you kill the outside bacteria making it safe to eat the pink insides since it won't be exposed to any bacteria. Hamburgers however are made of ground meat which, since it's ground, has been exposed to more bacteria. The meat is packed in a hamburger patty, but the inside has still been exposed to bacteria. You fully cook hamburgers to kill any lingering bacteria inside and out of the patty.
Answer:
Threshing may be done by beating the grain using a flail on a threshing floor. Another traditional method of threshing is to make donkeys or oxen walk in circles on the grain on a hard surface. A modern version of this in some areas is to spread the grain on the surface of a country road so the grain may be threshed by the wheels of passing vehicles.
Explanation:
Hoped this helped! :D