That portion of the ionosphere existing between approximately 160 and 400 km above the surface of the Earth, consisting of layers of increased free-electron density caused by the ionizing effect of solar radiation. Note 1: The F region reflects normal-incident frequencies at or below the critical frequency (approximately 10 MHz) and partially absorbs waves of higher frequency. Note 2: The F1 layer exists from about 160 to 250 km above the surface of the Earth and only during daylight hours. Though fairly regular in its characteristics, it is not observable everywhere or on all days. The principal reflecting layer during the summer for paths of 2,000 to 3,500 km is the F1 layer. The F1 layer has approxiÂmately 5 ´ 105 e/cm3 (free electrons per cubic centiÂmeter) at noontime and minimum sunspot activity, and increases to roughly 2 ´ 106 e/cm3 during maxiÂmum sunspot activity. The density falls off to below 104 e/cm3 at night. Note 3: The F1 layer merges into the F2 layer at night. Note 4: The F2 layer exists from about 250 to 400 km above the surface of the Earth. The F2 layer is the principal reflecting layer for HF communications during both day and night. The horizon-limited distance for one-hop F2 propagation is usually around 4,000 km. The F2 layer has about 106 e/cm3. However, variations are usually large, irÂregÂular, and particularly pronounced during magnetic storms.
good thing there are like 10 people in the world who know what that means
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crew slang:
park in northern virginia, run by the Northern Virginia Regional Park Authority. Its right on the occoquan sewage dump (a.k.a. occoquan reservoir)
place were all the good crew teams practice (or in the case of TJ crew, sit around and play on thier TI-83s). Also the site of the NCASRA crew races. Good place with lots of good memories.... also where fairfax crew owns all.
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A computer program that erases data and/or programs from a computer system's memory, usally with malicious intent.
I got the w32.blaster.worm but i have Norton Antivirus so it wasn't a problem.
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The real intent of the Fire Drill is to prepare the students of Fairfax High School for a real fire (i.e. people setting trash cans on fire). But it in reality, its just a social hour.
I didn't do my chemistry homework, but thanks to the fire drill, my teacher didn't have time to check.
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1) The Very High Frequency communcations band from 26.985 to 174 MHz or 30 to 300 MHz, the most popular local (less then 200 mile range) communication band
2) the VHF-AM civilian aircraft communcation band 118 to 137 MHz
see UHF
"Roger, we got you on VHF 122.9"
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A high-quality, relatively low-risk investment; the term usually refers to stocks of large, well-established companies that have performed well over a long period.
I just put $500 on some good GE blue chip stock.
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Ummmmm.......i dont think the engine is supposed to be doing that........(impact sound)
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