D. single- and simple multi-celled organisms
Although more complex animals like invertebrates and multi-celled organisms began to appear, it was very late compared to the original, simpler organisms for which the Precambrian time is characterized by.
Crop rotation improves soil fertility
Answer:
<em> clouds </em><em> have an important effect on Earth's temperature. But it's a bit complicated: Clouds can both cool down and warm up the temperatures on Earth. Clouds can block light and heat from the Sun, making Earth's temperature cooler.</em>
Explanation:
<em>Hope</em><em> It</em><em> Help</em>
