.... they had to be entered by turning dials. It was designed to help Pascal's father who was a tax collector. In the early 1800's, a mathematics professor named Charles Babbage designed an automatic calculation machine. It was steam powered and could store up to 1000 50-digit numbers. Built in to his machine were operations that included everything a modern general-purpose computer would need. It was programmed by--and stored data on--cards with holes punched in them, appropriately called "punchcards". His inventions were failures for the most part because of the lack of precision machining techniques used at the time and the l .....

.... herbivore’s because they have to break down cellulose, which takes a longer time. (Giffard R. & Nat, M 1986) This concludes my study on the digestion system of the frog. FROG'S CIRCULATORY SYSTEM A frog has a closed circulatory system just like humans. This means blood is always enclosed in blood vessels as it circulates the organisms body. Blood also circulates more rapidly and efficiently through a closed circulatory system. It consists of a very well developed system of arteries, veins and capillaries that reach all the living cells of an organism. (Cooper, H., Hays, S., Walker D., Linden R. 1982) The frog’ .....

.... Darwin believe that it happens based on chance or natural selection. Whatever you believe or disbelieve, life cannot be planned. No matter how hard a person attempts to "plan" their path in life, it is by chance and luck where that path takes us. Darwin's career was also based on chance, not planning. Darwin never planned to become a scientist or the father of natural selection. It was by pure chance that he obtained the job on the voyage of the Beagle, which started his career. Darwin stated about this voyage that, "The voyage of the Beagle has been the by far the most important event in my life and has determined my whole .....

.... operations to be carried out with the same equipment: evaporation of the waste solution mixed with the ------------------------------------------------------------ 1) borosilicate: any of several salts derived from both boric acid and silicic acid and found in certain minerals such as tourmaline. additives necesary for the production of borosilicate glass, calcination and elaboration of the glass. These operations are carried out in a metallic pot that is heated in an induction furnace. The vitrification of one load of wastes comprises of the following stages. The first step is 'Feeding'. In this step the vit .....

.... a picture of what the lives of past civilizations were like, the act of digging up such artifacts can be considered immoral. A person claiming to be conducting an archeological study in a present-day cemetery would most definitely be apprehended and punished for his actions. Cemeteries are considered sacred places, and those who violate the laws made to protect them will be punished for their actions. There is no difference between the aforementioned act and that of unearthing sacred Native American burial grounds, for example. Great care was taken to ensure that the dead received proper and sacred burials in past civilizat .....

.... size, shape, color and hardness. Often are mistaken for bones, fossils, meteorites and other odd objects. They can be so small that it requires a magnifying glass to be visible or as large as 10 feet in diameter and weigh hundreds of pounds. can also have somewhat of regular shapes such as boxes, blocks, flat disks, pipes, cannon balls and have even been known to resemble parts of a human body such as a foot or ribs. are most commonly composed of calcite but sometimes can be composed of iron oxide or iron hydroxide such as goethite. But also can be composed of other minerals ranging from siderite, ankerite, dolomite, pyrit .....

.... of dead relatives, dancing around in the sky, while the Vikings believed that they were caused by a fire on the edge of the world. In the fourteenth century, Aristotle described the auroras as jumping goats caused by the earth=s vapours being set on fire by meteors. Later on, in 1707, a Norwegian physicist claimed that they were caused by steam and smoke that escaped from a heat source beneath Greenland. It was not until the late 1950's that scientists finally discovered the true cause of the aurorasC Solar Wind. Solar Wind Approximately every eleven years, explosions erupt from sun spots creating what are called Solar Flar .....

.... the flow of oxygen to the bloodstream, and could harm people with heart disease. Nitrogen oxide is formed when a car engine gets hot. It contains chemicals that aid in the formation of ground level ozone as well as acid rain (2 factsheet, OMS-5). Acid rain destroys the outsides of buildings, statues, etc. Acid rain can also contaminate drinking water, damage vegetation, and destroy sealife. These two pollutants are two of the most dangerous pollutants released through car exhaust. If these two pollutants were cut down just a little bit our planet would be a safer place to live. Carbon dioxide is another gas released throug .....

.... but in insulators and semiconductors there is an "energy gap", in which no electron orbits can exist, between the inner valence band and outer conduction band [Book 1]. Valence electrons help to bind together the atoms in a solid by orbiting 2 adjacent nucleii, while conduction electrons, being less closely bound to the nucleii, are free to move in response to an applied voltage or electric field. The fewer conduction electrons there are, the higher the electrical resistivity of the material. In semiconductors, the materials from which solar sells are made, the energy gap Eg is fairly small. Because of this, electrons in the va .....

.... a lot of craters. The craters, which cover seventy-five percent of Mercury’s surface, were formed by huge rocks that smashed into the planet’s surface. The largest crater is called the Caloris Basin and it is 1400 km in diameter and is flooded with molten lava. Mercury also has many cliffs that are usually over 300 miles long and two miles high. The rest of the planet’s surface is smooth and may have been formed by lava flowing out of cracks in the surface. Temperatures on Mercury vary greatly because of it’s closeness to the sun. The surface temperature on the sunlit side is about 430 degrees Celsius, while the dar .....