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Solar concentrating technologies such as parabolic dish, trough and Scheffler reflectors can provide process heat for commercial and industrial applications. The first commercial system was the Solar Total Energy Project (STEP) in Shenandoah, Georgia, USA where a field of 114 parabolic dishes provided 50% of the process heating, air conditioning and electrical requirements for a clothing factory. This grid-connected cogeneration system provided 400 kW of electricity plus thermal energy in the form of 401 kW steam and 468 kW chilled water, and had a one-hour peak load thermal storage. Evaporation ponds are shallow pools that concentrate dissolved solids through evaporation. The use of evaporation ponds to obtain salt from sea water is one of the oldest applications of solar energy. Modern uses include concentrating brine solutions used in leach mining and removing dissolved solids from waste streams. Clothes lines, clotheshorses, and clothes racks dry clothes through evaporation by wind and sunlight without consuming electricity or gas. In some states of the United States legislation protects the "right to dry" clothes. Unglazed transpired collectors (UTC) are perforated sun-facing walls used for preheating ventilation air. UTCs can raise the incoming air temperature up to 22 C (40 F) and deliver outlet temperatures of 4560 C (113140 F). The short payback period of transpired collectors (3 to 12 years) makes them a more cost-effective alternative than glazed collection systems. As of 2003, over 80 systems with a combined collector area of 35,000 square metres (380,000 sq ft) had been installed worldwide, including an 860 m2 (9,300 sq ft) collector in Costa Rica used for drying coffee beans and a 1,300 m2 (14,000 sq ft) collector in Coimbatore, India, used for drying marigolds.
What are some examples of solar concentrating technologies?
A: parabolic dish, trough and Scheffler reflectors

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After the Romans left, Britain was invaded by Anglo-Saxon peoples. By AD 600 they had established control over much of what is now England, but Somerset was still in native British hands. The British held back Saxon advance into the south-west for some time longer, but by the early eighth century King Ine of Wessex had pushed the boundaries of the West Saxon kingdom far enough west to include Somerset. The Saxon royal palace in Cheddar was used several times in the 10th century to host the Witenagemot. After the Norman Conquest, the county was divided into 700 fiefs, and large areas were owned by the crown, with fortifications such as Dunster Castle used for control and defence. Somerset contains HM Prison Shepton Mallet, which was England's oldest prison still in use prior to its closure in 2013, having opened in 1610. In the English Civil War Somerset was largely Parliamentarian, with key engagements being the Sieges of Taunton and the Battle of Langport. In 1685 the Monmouth Rebellion was played out in Somerset and neighbouring Dorset. The rebels landed at Lyme Regis and travelled north, hoping to capture Bristol and Bath, but they were defeated in the Battle of Sedgemoor at Westonzoyland, the last pitched battle fought in England. Arthur Wellesley took his title, Duke of Wellington from the town of Wellington; he is commemorated on a nearby hill by a large, spotlit obelisk, known as the Wellington Monument.
What rebellion took place in Somerset in 1685
A: Monmouth Rebellion was played out in Somerset and neighbouring Dorset

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The use of alloys by humans started with the use of meteoric iron, a naturally occurring alloy of nickel and iron. It is the main constituent of iron meteorites which occasionally fall down on Earth from outer space. As no metallurgic processes were used to separate iron from nickel, the alloy was used as it was. Meteoric iron could be forged from a red heat to make objects such as tools, weapons, and nails. In many cultures it was shaped by cold hammering into knives and arrowheads. They were often used as anvils. Meteoric iron was very rare and valuable, and difficult for ancient people to work.
What kind of iron was readily available to people?
A: unanswerable

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The roots of hard rock can be traced back to the 1950s, particularly electric blues, which laid the foundations for key elements such as a rough declamatory vocal style, heavy guitar riffs, string-bending blues-scale guitar solos, strong beat, thick riff-laden texture, and posturing performances. Electric blues guitarists began experimenting with hard rock elements such as driving rhythms, distorted guitar solos and power chords in the 1950s, evident in the work of Memphis blues guitarists such as Joe Hill Louis, Willie Johnson, and particularly Pat Hare, who captured a "grittier, nastier, more ferocious electric guitar sound" on records such as James Cotton's "Cotton Crop Blues" (1954). Other antecedents include Link Wray's instrumental "Rumble" in 1958, and the surf rock instrumentals of Dick Dale, such as "Let's Go Trippin'" (1961) and "Misirlou" (1962).
Who was the Memphis hard rock guitarist known for using power chords?
A:
unanswerable