The correct answer is option D, that is, ice floating on the water surface.
The cohesive forces among the molecules of a liquid are accountable for the process called surface tension. Surface tension refers to the tension of the surface film of a liquid resulting due to the attraction of the particles in the surface layer by the bulk of the liquid that seems to reduce the surface area.
The examples of surface tension are walking of small insects on water, floating of a needle, the surface tension of water offers the essential wall tension for the creation of bubbles with water, and surface tension is accountable for the shape of liquid droplets.
The low density of ice makes it float at the liquid water surface, like ice cubes in a glass of water, or an iceberg. The lower density of water in its solid form is because of the way hydrogen bonds are aligned as it freezes, the water molecules are pushed further far away in comparison to the liquid water.
In many regions, wetlands have been filled in so as to be able to use the land for farming. Wetlands are vital for reducing the intensity of floods, as they tend to hold back some of the water. Without wetlands, flood will tend to wash increased sediment and pollutants into the ocean, which can have a detrimental effect on marine life. Coastal developments can also have a negative effect on marine life. The removal or moving of beach sand is in particular damaging to intertidal organisms that depend on specific coastal environments, and rocky shores can be smothered by sand, whereas sand environments can change into bare rocky environments. Impounding of rivers and reduced river flow can result in estuaries becoming closed. Many marine organisms, such as fish, depend on estuaries as nursery areas where they lay their eggs. Reduced opening of estuaries means that many fish species cannot reproduce. Built harbours result in changed currents and alteration of the sea floor, which also disrupts marine ecosystems.
The answer is cancer drugs. According to a united nations University Report, almost 62 percent of all discovered and distributed cancer drugs have been made or derived from the discoveries of medicinal plants. Cancer Drugs are usually made from Medicinal Plants, because they contain more effective effects than other substances.
Answer:
Explanation:
The physical evidence that suggest an increase in both respiratory and circulatory rate of a runner is that his/her heart beat ( pulse) iinreases significantly and the runner breathes heavily in other to let in more air into his/her body.