<em><u>i</u></em><em><u> </u></em><em><u>guess</u></em><em><u> </u></em><em><u>its</u></em><em><u> </u></em><em><u> </u></em><em><u>Japan's economy</u></em><em><u> </u></em><em><u>slowed</u></em><em><u> substantially in the 1990's</u></em>
<span>Seafloor spreading is caused by diverging plates. </span>
You didn’t give any options but i’m assuming it’s “oxygen”
One reason is that the plates float on a hot boiling mentle. when the heat rises and the mentle expands the plates above it also moves.
the other reason is that the plates themselves move.plates have warmer inner sides that tend to rise. and colder outer side that tends to sink. this tug of war between the hotter and colder sides of the plate also helps them move.
