The electromagnetic wave is self propagating, what I mean by that is, an electric field generates a magnetic field at 90 degree phase angle, and the magnetic wave you get as a result generates the electric wave at the same phase angle. The interchange of electric to magnetic and vice versa continues and lets the electromagnetic waves to travel without any medium. Quite interesting, really!
Answer: I think the second line is correct it you put a apostrophe in the first and before Simpson.
Explanation: The third line is also correct it is a I;I compound sentence. But the first line has some mistakes.
It depends on what type of plastics we're dealing with.
Let's take plastic bags for instance:
The advantages of plastics: It is durable, low cost, water resistant, lesser energy and heavy chemicals requirements in manufacture and are light weight. Many studies comparing plastic versus paper for shopping bags show that plastic bags have less net environmental effect than paper bags, requiring less energy to produce, transport and recycle; however these studies also note that recycling rates for plastic are significantly lower than for paper.Plastic carrier bags can be reused as trash bags or bin bags. Also, plastic bags are complimentary in many locations but are charged or "taxed" in others.
The disadvantages of plastics: Plastics bags are make of a non-renewable resource, which gives us more reasons to use recyclable shopping bags. Plastic bags are also flimsy and do not sit as well as either paper or cloth. They are a hazard to wildlife animals, if they are not disposed properly. Lastly, plastic bags clogs roadside drains, which could cause the flooding of the street at heavy rainfalls.
