Why do the two hemispheres of the brain control the opposite sides of the body?

In which situations is the principle of cross-cutting relationship useful in determining relative age?

Penelope studies how the structure and function of the nervous system is related to behavior. she is a psychologist

Which of the following statements is most likely correct about a rock belonging to the jurassic age and a rock belonging to the cambrian age? options: 1) they have identical fossils of organisms that have evolved over time. 2) both have animal fossils preserved in them due to weathering and erosion. 3) they contain different fossils because life on earth has changed through time. 4) the fossils in them were formed on the surface of earth due to exposure to sunlight.