Final answer:
The displacement of the jogger is 70 meters west, as displacement is a vector quantity calculated by subtracting the distance covered in the opposite direction from the total distance in one direction.
Step-by-step explanation:
If a jogger runs 100 meters west and then turns around and runs 30 meters east, her displacement is the difference in these two distances in a straight line. Displacement is a vector quantity, which means it has both magnitude and direction. Since the west and east are opposite directions, we subtract when calculating the displacement.
To find the jogger's displacement, we subtract the distance ran eastward from the distance ran westward. So, the displacement is 100 meters west − 30 meters east = 70 meters west. Therefore, the correct answer is C) 70 meters west.