Answer:
D) Rare-earth elements
Explanation:
Rare-earth elements are elements that are highly limited in supply, may be depleted (used up) within a short time, and are difficult to replenish. Examples include neodymium, samarium, and yttrium.
Paper can be replenished by recycling old papers, while solar energy and water are renewable energy sources because we can not use them up within the foreseeable future.
Answer: c. Bird droppings that contain seeds from a different location
Answer:
I think the answer is C
''Reusing plastic bags''
Explanation:
Removing carnivores from a forest has a great impact on a environment since the population of the herbivores will increases drastically and the dynamic equilibrium of the area will be greatly effected.
If we look at choice B '' Heating homes with fossil fuels'', this will also have a big impact on the earth since fossil fuels are non-renewable and take centuries to form. Heating homes with them will result in loss of fossil fuels.
Now let's look at choice D ''Adding heavy metals to the water supply''. Heavy metals are dangerous to the human health and even cause cancer. This will cause thousands of deaths and will also have a great impact on the global stability.
This leaves choice C ''Reusing plastic bags''. This will cause less pollution and less harm to wildlife but doesn't have any big threat to the global stability. As in changing the world population or causing deaths in large numbers.
so I think choice C is the answer
It would be B.
It depends on the cloning technique. The reproductive cloning procedure starts with extracting small samples of tissue from the subject that will be cloned. Then culture the tissues in a lab. Condition the cultured cells so it halts cell division. The G0 phase of the cell cycle then begins which selects a cell for such cloning, then step B comes into play
In the light-independent reactions or Calvin cycle, the energized electrons from the light-dependent reactions provide the energy to form carbohydrates from carbon dioxide molecules. The light-independent reactions are sometimes called the Calvin cycle because of the cyclical nature of the process.