If you were to make a cross section of the body through the diaphragm which body cavities would you separate ?

If we (hypothetically) cut a body through the diaphragm (in the transverse plane), then the two body cavities that will be separated will be the thoracic cavity, lined by the pleura and encases thoracic organs such as the heart and lungs; and the abdominal cavity, lined by the peritoneum and encases abdominal organ such as the liver, spleen, stomach, and intestines. 

No because the eaeht is on a 23.5 degree axis tilt and so when it is winter the northern hemisphere is pointing away from the sun and the soutubern hemisphere is pointing toward the sun