Because freezing will often burst the cell walls and destroy tissue. The crystals of ice are very sharp and hard to control AFAIK. Note what happens to a banana or many types of fruit after you dethaw — it becomes all mushy and not of the same structure, fiber and cell form as before, like a bad beam up in Star Trek.
Answer:
<em>Moving</em><em> </em><em>of</em><em> </em><em>fan</em><em> </em><em>is</em><em> </em><em>convection</em><em>.</em>
<em>The faster moving air from the fan displaces the warmer air that is in direct contact with our skin. This enhances the rate of convective heat transfer, which means we feel cooler.</em>
The answer would be: <u>Molten material that cooled quickly.</u>
Igneous rocks are formed by the cooling of molten material. So we can cross out the last two choices. The rock has no identifiable crystals so it is most likely an Extrusive igneous rock. They form on the surface where they cool quickly.
Those that form underground are called intrusive rocks. They cool slowly allowing enough time for crystal formation.
