Essay editing needed, please help

<p>My SAT is coming up and i really suck at the timed essay. Here is one of the practice essays I wrote based on a previous test topic. Please read this and tell me where I could improve and give me some tips as to how to write a better timed essay.</p>

<p>Topic:Does progress reduces the number of problems in the world or does solving old problems just lead to new one?</p>

<pre><code> The world is constantly changing. New ideas are formed everyday, and the practical application of these ideas often results in solving a problem. However, just because a problem is solved does no mean that there is one less problem in the world. Rather, that problem, which was resolved is simply replaced by a new one, born from the resolution of the old one. The evidences found in medicine, history, and literature are pervasive.
The medical field has come long way since the dark ages, when doctored used leeches and blood-letting as preferred methods of treatment. With advances in technology, chemistry, and biology, doctors now are able to create anti-biotics designed specifically to attack and destroy bacteria. With this innovation, bacterial caused syndromes became easier to treat. However, to the chagrin of many scientists, it has been discovered that these anti-biotics have given birth to new strains of bacteria tougher then their predecessors. These new bacteria are known as "superbugs". They are incredibly dangerous and have already claimed many lives because they are resistant to the current treatments. Therefore, by creating a better way to deal with bacteria, we have given rise to a more rare strain that is even more deadly then the previous.
Another case is the resolution of the American Civil War. The Civil war was a fight between the northern Union and the Southern Confederate. When the war finally ended, winner, north, faced a new problem. Although they managed the subjugate the southern dissenters, we have to now find a way to ease those rebellious back into the Union. Thus, by resolving the issue of succession, the new issue of Reconstruction appeared.
A third example is found in the classic Chinese literature "The Three Kingdoms". When Cao Cao lead his army against the nascent Lin kingdom, the ruler of Lin appealed to the Wu kingdom for support. A treaty was quickly signed and a temporary alliance was formed. When the battle began, the alliance, despite being militarily inferior, managed to defeat Cao Cao. Cao Cao, snatching defeat from the jaws of victory, was forced to cease belligerent actiosn so that he could recuperate and rebuild his forces. However, not all was well. The Wu kingdom, after seeing the military abilities of the Lin kingdom, began to perceive them as a threat and started a campaign against them as soon as the alliance was dissolved. Thus, although the Lin managed to defeat Cao Cao, they now have to contend with a new enemy.
From these examples, it is obvious that solving problems only create new headaches. the number of problems will never diminish. It is a never ending cycle of replacement.
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