B
The wastes are radioactive and can cause cancer. This is the #1 reason according to my research why it is important to dispose of nuclear waste.
        
                    
             
        
        
        
With the advent of industrialization, several trees have been cut at an alarming rate for raw materials and various other purposes. This felling of trees can be regulated by selective cutting, clear-cutting and shelterwood cutting.
Forest fires are one of the common causes of loss of forests. Sometimes the forest land is set on fire to make the land available for commercial purposes. Once cleared, there can be no vegetation. Natural forest fires are also responsible for the destruction of huge forest covers. Latest fire fighting techniques should be adopted to conserve the forest. However, forest fires are an important part of the ecosystem and it helps replenish nutrients in the soil from dead and decaying matter.
More trees should be planted to increase the forest cover. Trees should be selected according to the geographical conditions of a particular region and proper care should be taken during the growth of trees.
Prevention of exploitation of forestry and forest products is necessary for the conservation of forest.
The existing forests should be protected from diseases by spraying chemicals, antibiotics or development of pest-resistant strains of trees.
 
        
             
        
        
        
Hi there!
<u>Electronegativity</u> is the concept of how likely an atom is to attract the shared molecules in one of these bonds to itself. We know the molecule water is made up of two hydrogens and one oxygen. The electronegativity of hydrogen is 2.2, and oxygen 3.4. An <u>ionic bond</u> needs at least a difference in electronegativity of 1.6. As the difference is less than that, we can say that water is a covalent molecule. This then wipes out choice B, because it is not ionic, and C, as we have seen it is actually covalent.
Now, we can see the difference in electronegativity between oxygen and hydrogen is still 1.2. This means that while it is not at the point for there to be an ionic bond, there is still a difference in attraction, where the electrons will tend to favor the oxygen more and 'hang around it' more. As electrons are <u>negatively charged</u><em><u>,</u></em> this means that the oxygen will gain a slightly negative charge. This then makes the molecule polar, because it now has a charge within the molecule. This means we have our answer, choice D.
In terms of hydrophobic molecules - they tend to be ones without a charge. (If you're interested in this kind of stuff, I'd search hydrophobic up, and possibly also look into hydrogen bonds).
Hope this helps! Feel free to ask me any other questions you have about this specific problem.
 
        
             
        
        
        
Answer:
The alveolar walls and capillary walls share a membrane. That's how close they're getting. This allows oxygen and carbon dioxide to readily pass from the respiratory system to the circulation. Oxygen molecules bind to red blood cells as they return to the heart.
 
        
             
        
        
        
Chemosynthesis is the biological conversion of one or more carbon- containing molecules.