Which of the following is a scientific theory related to Earth Science? (mark all appropriate options) Select one or more:
a. Big Bang Theory
b. Plate Tectonics
c. Theory of Relativity
d. Giant Impact Theory

When it is summer at the south pole, a. the northern hemisphere is tilted toward the sun. b. the southern hemisphere is tilted away from the sun. c. the northern hemisphere is tilted away from the sun. d. both the southern and northern hemispheres are tilted toward the sun.