<span>Some 120 prescription drugs sold worldwide today are derived directly from rainforest plants. And according to the U.S. National Cancer Institute, more than two-thirds of all medicines found to have cancer-fighting properties come from rainforest plants. Examples abound. Ingredients obtained and synthesized from a now-extinct periwinkle plant found only in Madagascar (until deforestation wiped it out) have increased the chances of survival for children with leukemia from 20 percent to 80 percent.</span>
This is called a chemical bond.
Answer and Explanation:
Both clouds and fog are closely related to precipitation.
This can be explained first by the formation of clouds and fog, which begin when the air contains water vapor. This <u>water vapor is produced when there is an accumulation of moisture in the enviroment which leads to the formation of clouds. A similar process occurs with the formation of fog, which comes from saturation, that occurs after the evaporation and condensation processes that take place after precipitation (water cycle). </u>
Moreover, some types of clouds (cumulonimbus) are associated with precipitation as they could be accompanied by climatic phenomenon such as rain and snow.
