The sclerenchyma is the tissue in which creates the plant firm and hard. The two kinds of sclerenchyma cells exist fibers and sclereids. Their cell walls be made up of cellulose, hemicellulose and lignin. The sclerenchyma cells are the principal associate cells in plant tissues that have come to a close elongation.
The answer for the given question above would be option C. GRAVITATIONAL FORCE. Based on the given scenario above of a leaf that falls to the ground when Tonya let it go, the force that pulled the leaf to the ground is the gravitational force. This kind of force is a force <span>that attracts any object with mass. Hope this helps.</span>
A) The stars core shrinks
The star will contract under the weight of gravity.
When it contracts it will heat up and expand to a red giant.
When the star runs out completly of helium it would emit gasses and form a star nebula.
It would then become a white dwarf then into a black dwarf.
You could cover the sand dunes with tarps that are attached into the ground with stakes, or routinely spray them with lots of water to make the sand heavier and less likely to be picked up by wind.