Answer: D. Acid from abandoned mines
Explanation:
Point source pollution can be define as the pollution that can be caused by a pollutant whose source of origin is known. As the source of origin is known the path of the pollutant can be traced back to it's origin hence, the pollution can be controlled.
Among the options given, D. Acid from abandoned mines. is the correct option this is because of the fact that the source of origin of the pollutant is known that is abandoned mines.
Quickly... this is a harder one, because all of possible answers are the result of interactions over a long time. However, these change the surface of the earth the fastest
1.) Volcanoes
2.) Flooding
Over a long time
1.) Through the rock cycle... earthquakes, mountain forming, etc.
2.) Melting, or forming of ice... changes sea levels
Educate your family about endangered species in your area.
Recycle and buy sustainable products.
Recycle and buy sustainable products.
Reduce your water consumption.
Volunteer. If you don't have money to give, donate your time
Answer:
<u>Light microscope</u>:
- use a beam of light to produce magnified images
- can be used to examine living cells and tissues
<u>Scanning electron microscope</u>:
- use a beam of electrons to produce magnified images
- can be used to examine DNA
- can be used to examine cells
<u>Transmission electron microscope</u>:
- use a beam of electrons to produce magnified images
- can be used to examine DNA
- can be used to examine cells
Explanation:
Light microscope: is a commonly used microscope also known as compound microscope. Magnifies images from 40X upto 1000X. It uses ray of visible light to produce a magnified image. The light microscope can be used to view specimen of both living and dead cells or tissues. However, it doesn't give a detailed view of a specimen like electron microscope.
Scanning electron microscope: It uses electron beam as an illuminating source. It has a much higher resolving power than light microscope because it uses electrons instead of light. It magnifies object upto 500000 times the actual size. Internal structures can also be viewed. However, only dead specimen can be used because the beam of electrons can kill the cells. They are of two types:
- <u>Scanning electron microscope(SEM): </u>an electron beam passes over the specimen's surface and displaces electrons which are then focused on a screen to form an image. Images appear in 3-D
- <u>Transmission electron microscope: </u>electromagnets magnify the image by passing beam of electrons through a thin specimen. Images appear in 2-D