Company that invests the funds of its subscribers in diversified securities and issues units representing shares in those holdings. It differs from an investment trust, which issues shares in the company itself. While investment trusts have a fixed capitalization and a limited number of shares for sale, mutual funds make a continuous offering of new shares at net asset value (plus a sales charge) and redeem their shares on demand at net asset value, determined daily by the market value of the securities they hold.
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Group of a prescribed size with a specific combat role within a larger military organization. The chief units in the ancient world were the Greek phalanx and the Roman legion. Modern units originated in the 16th–18th century, when professional armies reemerged in Europe after the end of the Middle Ages. Since then the basic units—company, battalion, brigade, and division—have remained in use. The smallest unit today is the squad, which has 7–14 soldiers and is led by a sergeant. Three or four squads make up a platoon, and two or more platoons make up a company, which has 100–250 soldiers and is commanded by a captain or a major. Two or more companies make up a battalion, and several battalions form a brigade. Two or more brigades, along with various specialized battalions, make up a division, which has 7,000–22,000 troops and is commanded by a major general. Two to seven divisions make up an army corps, commanded by a lieutenant general, which with 50,000–300,000 troops is the largest regular army formation, though in wartime two or more corps may be combined to form a field army (commanded by a general), and field armies in turn may be combined to form an army group.
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Length of the semimajor axis of Earth's orbit around the Sun, 92,955,808 mi (149,597,870 km), often defined simply as the average distance from Earth to the Sun. Direct measurement through the parallax method cannot be used for accurate determinations, because the Sun's glare blots out the light of the background stars necessary to make the measurement. The most precise values have been obtained by measuring the distance from Earth to other objects orbiting the Sun. This indirect method requires an accurate proportional mathematical model of the solar system; once the distance to one planet or other object is determined, then the distance to the Sun can be calculated.
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The gauss, abbreviated as G, is the cgs unit of magnetic field B (which is also known as "magnetic flux density" and "magnetic induction"), named after the German mathematician and physicist Carl Friedrich Gauss. One gauss is defined as one maxwell per square centimetre.
The units for magnetic flux (Φ)—which is the product of magnetic flux density (B) and area (A), i.e., Φ = BA—are the weber (Wb) in the MKS system and the maxwell (Mx) in the CGS system. The conversion factor is 108, since flux is the product of flux density and area, area having the units of the square of distance, thus 104 (flux density conversion factor) times the square of 102 (linear distance conversion factor, i.e., centimeters per meter).