<span>
</span><span>the time or date (twice each year)
</span><span>when day and night are of equal length</span>
X would equal 5. (need more characters)
America is very beautiful.
Answer: The Earth is a closed system for matter
That is a list of all basic elemental materials on our planet. Because of gravity, matter (comprising all solids, liquids and gases) does not leave the system.
