According to scientists, many years ago their was a supercontinent called "Pangaea." As years went by, the continents slowly drifted apart which is what's today. However, from recent discovers, scientists predict that in about 250 millions years from now the continents will merge again, however this time, in a different order ("Pangaea Ultima"). So the answer to your question is D.
Hope this helps. :D
Answer:
That is the main difference between sexual and asexual reproduction. Sexual reproduction just means combining genetic material from two parents. Asexual reproduction produces offspring genetically identical to the one parent.
<span>The correct answer is b.0.5 to 1 micrometre thick.</span>
Usually, the respiratory membrane is about 0.6 micrometres thick. This membrane consists of the alveolar epithelial cells, the capillary endothelial cell, and basement membranes which are formed by the alveolar and capillary cells.