Answer:
1. On the day of an equinox, daytime and nighttime are of approximately equal duration all over the planet. They are not exactly equal, however, due to the angular size of the Sun, atmospheric refraction, and the rapidly changing duration of the length of day that occurs at most latitudes around the equinoxes
2. the four seasons at the higher altitudes are caused by the earths 23.5 ° tilting on its axis.
The seasons on the north and south pole remains constant while those at the latitudes the angle of the suns rays changes all through out the year which is enough to make variations in the day/night cycle temperatures that we call seasons.
3. seasons changes because:
*variation in the suns radiation angle due to the tilt of the earths axis.
*due to the earths axis that is tilted relatively to its orbital plane.
