.... pollutants into the atmosphere. The cleanest, cheapest, and least polluting power plant of the two types is the hydroelectric power plant. The main reason most countries use thermal versus the hydroelectric is because their countries don't have enough concentrated water to create enough energy to generate electricity. (World Book vol. 14, 586) plants generate only about eleven percent of the world's electricity. There are around 316 plants in the world that create 213,000 megawatts of electricity. (INFOPEDIA) Radioactive, or nuclear, waste is the by-product of nuclear fission. Fission occurs when atoms' nucleus' split and cause a nuclear reacti .....

.... into the water to form sulphuric acid. The rest comes from various oxides of nitrogen (mainly NO2 and NO3, collectively called NOx). These gases are produced almost entirely from burning fossil fuels, mainly in power satations and road transport. (Kucera, (1973) The Challenge of Ecology, The Mosby Company.) Tremendous quantities of this nitric acid and sulfuric acid mix are reflected in the lowering of the acidity of rain. Earthworms (Annelids) are a species of worm which are many segmented. They live in damp soil, usually forming intricate tunnels beneath the surface. Their bodies are lond and cylindrical, and have "bluntly tapered ends and .....

.... hours of calm, where people go to sleep, or stay in a half awake state. (During this stage, nothing seems to bother the person. Heroin is the most addictive narcotic. Of all narcotic addicts, 90-95% use heroin. In the United Stated alone, there are between 500,000- 750,000 heroin addicts. Heroin is often mixed with cheaper substances, so that the dealer can make a larger profit. Since addicts don't know about the purity of a substance, many die because of overdoses. In an overdose of heroin, the lungs stop functioning, and the person dies from lack of air. There can be other effects of heroin addiction, one is that people who have illnesses may .....

.... Though his theory has some errors, these theories are the basis for our understanding of atoms and chemistry. One mistake of Dalton was his belief that atoms were round and hard. This became the primary ambition for scientists after Dalton, to find out the structure of an atom. In 1897, Joseph John Thomson discovered electrons. Using a tube, magnets and charged plates, he sent ray particles through various experiments changing the position of the charged plates. By changing the plates, he discovered he could also change the point at which the particles would hit a florescent screen at the end of the tube. He decided that the ray was mad .....

.... back to a single, inconceivably dense point concluding the life of the universe. You would think of this as the end, but only an explosion is needed to wake up and give life to a new universe. Therefore, trapped forever in the cycle of rebirth. As humans we also travel through a cycle of rebirth according to the Hindu religion. We are all trapped on the Wheel of Samsara trying to break free. It is only possible to escape through the laws of Karma. Karma is simply how you act in this life determines what you are after your rebirth. For example, if you live each life being the best Hindu you possible can eventually your soul or Atman w .....

.... group, and one of four different nitrogen containing compounds, also called bases. The four are adenine (A), guanine (G), thymine (T), and cytosine (C). The deoxyribose molecule occupies the center of the nucleotide, with the phosphate group on one side and a base on the other. The phosphate group of each nucleotide is also linked to the deoxyribose of the adjacent nucleotide in the chain. These linked deoxyribose-phosphate subunits form the side rails of the ladder. The bases face inward toward each other, forming the steps of the ladder. The nucleotides in one strand have a specific association with the corresponding nucleotides in the other st .....

.... The public switched telephone networks (PSTNs) expanded, but with the circuit switched transfer mode remaining in use. This is because it provided an obvious way of keeping the constant connection necessary for voice traffic. The invention of the transistor and the concept of pulse code modulation (PCM) allowed digital communications to be developed in the late 1960's. The interconnection of computer systems over telecommunication networks soon became a requirement. Modems were used at first to generate analogue signals compatible with the PSTNs from the digital computer data to allow such interconnections. The already wide spread use of the PSTNs .....

.... density, and where, as a result, the curvature of space-time is extreme. Moreover, the intense gravitational field of the black hole prevents any light or other electromagnetic radiation from escaping. But where lies the “point of no return� at which any matter or energy is doomed to disappear from the visible universe? The black hole's surface is known as the event horizon. Behind this horizon, the inward pull of gravity is overwhelming and no information about the black hole's interior can escape to the outer universe. Applying the Einstein Field Equations to collapsing stars, Kurt Schwarzschild discovered the critical radius for a given ma .....

.... requires energy because it is moving against the concentration gradient. In active transport the cell uses ATP to remove unwanted materials and to receive needed ones. For example a muscle cell wants potassium and wants to get rid of a sodium, the cell releases ATP to the pump proteins which results in the cell ejecting the sodium ion and at the same time another receptor cell accepts a potassium which is then released into the cell and the process is repeated until the cell is finished. c.Facilitated Transport In facilitated transport a molecule that cannot normally pass through into a cell use a carrier protein to gain access and e .....

.... discuss cost because it goes without saying: Linux wins the price to performance ratio. What is more important to discuss is the initial hardware and software fees, and maintenance and reliability which often go hand in hand. According to Sunworld, the estimated minimal required hardware costs that would go with a Linux machine is $200. In an NT machine, the minimal hardware cost rose up to $1300. This is because NT requires at least a 486 Pentium with 16MB of RAM. Linux can run fine on a 386 computer with only 8MB of RAM. What do the majority of users need a computer for? Mainly word processing and the use of a database program. An NT user do .....