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#1 Re: Exercises » Compute the solution: » Yesterday 00:30:56

Good work!

821. If

is a perfect square, then find the value of 'a'.

#2 Re: This is Cool » Miscellany » Yesterday 00:15:23

842) Songbird

Songbird, also called passerine, any member of the suborder Passeri (or Oscines), of the order Passeriformes, including about 4,000 species—nearly half the world’s birds—in 35 to 55 families. Most cage birds belong to this group. Songbirds are alike in having the vocal organ highly developed, though not all use it to melodious effect. Classification in this suborder is much disputed. Alaudidae (larks) and Hirundinidae (swallows) are the most distinctive families.

Songbirds range in size from tiny kinglets and sunbirds to comparatively large crows. They are mainly land birds that live in a wide variety of situations, from open grassland to forest. Although songbirds include some of the best songsters, such as thrushes, some have harsh voices like crows, and some do little or no singing. Songbirds are distinguished from other perching birds by certain anatomical characteristics, especially the more complicated vocal organ, or syrinx.

The syrinx—as the voice-producing structure, or song box, is called—is located at the point where the windpipe divides into two bronchial tubes to go to the lungs. The syrinx is an intricately constructed organ with a firm bony framework and filmlike vibrating internal membranes over which the air, during exhalation, passes rapidly, producing all the many utterances of the bird. A variable number of syringeal muscles and their controlling nerves adjust the tension on the membranes. The song box reaches its greatest complexity in the true songbirds. (But it is not a complicated syrinx alone that determines singing ability, for some true songbirds hardly sing at all). In some birds the windpipe is elongated and elaborately coiled. Sometimes this elongation is enclosed within the breast bone, or sternum. In certain of the birds-of-paradise known as manucodes, the elongated windpipe is coiled on the breast between the skin and the flesh. Presumably this lengthening of the windpipe gives resonance to the voice.

Vocalization in birds includes a wide variety of calls besides the song proper and provides a means of social communication. Bird song is best considered the vocalization that is used in courtship and breeding, chiefly by the male, to advertise that he is ready to mate, to attract the female and perhaps stimulate her,  to keep the pair together, and to inform rival males that he has established a territory from which they will be excluded. The male’s calls are also part of a threat display that takes the place of actual combat in repelling intruding rivals. However, similar song is sometimes given spontaneously when there is no obvious use for it. Occasionally females sing, and especially in tropical species pairs may duet, again perhaps as a method of reinforcing the bond between the pair. Often the song is delivered from a series of regularly used perches. Some species, especially those that live in grasslands, have flight songs.

Bird song need not be pleasing to the human ear. The hooting of the owl, the monotonously repeated phrases of the North American whippoorwill, the crazed, repeated whistle of a Malayan cuckoo that has given it the name of the brain-fever bird, and the African tinkerbird’s repeated notes, which, from their resemblance to hammering on metal, have given the bird its name—all must be called songs.

Which birds are the best songsters is a question that is subjective. The nightingale of Europe (Erithacus, or Luscinia, megarhynchos), a small thrush, perhaps heads the list of famous songsters of European literature. Also a favourite of the poets was the European skylark (Alaudia arvensis). In North America the mockingbird (Mimus polyglottos) is a wonderful performer with a rich, melodious, long-continued song. In Australia the lyrebirds, which are not true songbirds, have songs that are superlative in variety and intensity and have a dramatic quality. Though the best songsters may be true songbirds, some birds of other groups have pleasing or musical utterances, like the quavering trill of the screech owl and the cheery whistle of the bobwhite quail.

Songbird-400x400-1.jpg

#3 Re: Ganesh's Puzzles » Doc, Doc! » Yesterday 00:05:27

Hi,

#1558. What does the medical term 'Lymphopoiesis' mean?

#4 Re: Ganesh's Puzzles » Oral puzzles » Yesterday 00:05:04

Hi,

#4874. Three numbers are in the ratio 1 : 2 : 3. By adding 5 to each of them, the new numbers are in the ratio 2 : 3 : 4. Find the numbers.

#5 Re: Ganesh's Puzzles » General Quiz » Yesterday 00:04:41

Hi,

#7715. What does the term 'Frigophobia' mean?

#7716. What does the term 'Gelotophobia' mean?

#6 Re: Ganesh's Puzzles » Trigonometry » 2020-12-02 03:20:36

Hi,

Good work!

T # 159. The angle of elevation of the top of a flag post from a point on a horizontal ground is found to be 30 degrees. On walking 6 meters towards the post, the elevation increased by 15 degrees. Find the height of the flag post.

#7 Re: Ganesh's Puzzles » English language puzzles » 2020-12-02 00:28:47

Hi,

#3753. What does the verb (used with object) extenuate mean?

#3754. What does the adjective exterior mean?

#8 Re: This is Cool » Miscellany » 2020-12-02 00:21:10

841) Gull

Gull, any of more than 40 species of heavily built web-footed seabirds of the gull and tern family Laridae (order Charadriiformes). Several genera are usually recognized for certain specialized gulls, but many authorities place these in the broad genus Larus. Conspicuous and gregarious, gulls are most abundant as breeders in the Northern Hemisphere, which has about 30 species in temperate to Arctic regions. They are mostly colonial ground nesters, and those that breed inland usually go to coasts in winter.

Adult gulls are mainly gray or white, with variable head markings. In breeding season the head is either pure white, black, gray, or brown; it becomes streaked or smudgy in winter. The bill is strong and slightly hooked and in some species shows a spot of colour. Bill and leg colours help to distinguish species, as do wing patterns.

Adaptable opportunists, gulls feed on insects, mollusks, and crustaceans on beaches; worms and grubs in plowed fields; fish along shores; and garbage from ships. Some of the larger gulls prey on the eggs and the young of other birds, including their own kind.

The herring gull (L. argentatus) is by far the most familiar of the Atlantic gulls. A bird of the Northern Hemisphere, it has a gray mantle, flesh-coloured legs and feet, and black-and-white-spotted wing tips. It was rare at the turn of the century, a casualty of the millinery trade, which used bird feathers as decorations in women’s hats. Legal protection and open garbage dumps helped it stage a spectacular comeback. Today some conservationists worry about these gulls’ depredations on the nests of other shorebirds.

Herring gulls are scavengers as well as expert thieves, boldly stealing food from other birds and sometimes snatching sandwiches out of beachgoers’ hands. They also hunt moles and even rabbits, hovering over their holes waiting for the quarry to appear. Often they eat mollusks, whose hard shells they crack by flying over a hard surface and dropping them in flight.

The black-headed gull (L. ridibundus), a dark-headed bird with crimson legs, breeds in Eurasia and Iceland, winters south in India and the Philippines, and commonly feeds in fields, where its chief food is insects. Bonaparte’s gull (L. philadelphia), of North America, has a black head and bill, a gray mantle, and pinkish to reddish legs. It builds a stick nest in trees and hunts for insects over ponds. In the winter it may plunge into the sea for fish. The California gull (L. californicus) of North America breeds inland and winters on the Pacific coast. This species is credited with having saved the crops of early Mormon settlers in the Salt Lake City region from destruction by the Mormon cricket, a long-horned grasshopper; it is the state bird of Utah. Franklin’s gull (L. pipixcan) breeds in large colonies on inland marshes of North America and winters on the Pacific coast of South America.

The glaucous gull (L. hyperboreus) is mostly white with pinkish legs and a yellow bill with a red spot. It inhabits northern seas, but sometimes it winters as far south as Hawaii and the Mediterranean. The great black-backed gull (L. marinus), with a wingspread of 1.6 metres (63 inches), is the largest gull. It occurs on the coasts of the North Atlantic.

The kelp gull (L. dominicanus) is a very wide-ranging black-backed species of the Southern Hemisphere, including Antarctica. The laughing gull (L. atricilla), a medium-sized bird with a black head, red bill, and red feet, often gives vent to a strident, laughing call. It breeds from Maine to northern South America and winters south in Brazil, often on fresh waters far inland. It is the only gull that breeds both in the Caribbean area and in the North Atlantic Ocean. With a wingspread of about 60 cm (24 inches), the smallest gull is the little gull (L. minutus), a black-headed species of Europe and occasionally North America.

The Pacific gull (L. pacificus) breeds in the region of Tasmania and southern Australia. The ring-billed gull (L. delawarensis) is common on inland lakes in North America and often gathers in large flocks to feed on plowed fields. The sooty gull (L. hemprichi) of the western Indian Ocean has a dark brown hood and a grayish brown mantle. Ross’s gull (Rhodostethia rosea) is an attractive pinkish white bird that breeds in northern Siberia and wanders widely over the Arctic Ocean. Abounding in the Arctic, Sabine’s gull (Xema sabini) has a forked tail and a habit of running and picking up food like a plover. The swallow-tailed gull (Creagrus furcatus) of the Galapagos Islands is a striking bird, the only gull with a deeply forked tail.

Lesser-black-backed-gull.jpg

#9 Re: Ganesh's Puzzles » 10 second questions » 2020-12-02 00:09:20

Hi,

#7859. If the cost price of 15 articles is equal to the selling price of 12 articles, find gain percent.

#10 Re: Dark Discussions at Cafe Infinity » crème de la crème » 2020-12-02 00:06:45

790) Artturi Ilmari Virtanen

Artturi Ilmari Virtanen, (born Jan. 15, 1895, Helsinki, Russian Finland—died Nov. 11, 1973, Helsinki, Fin.), Finnish biochemist whose investigations directed toward improving the production and storage of protein-rich green fodder, vitally important to regions characterized by long, severe winters, brought him the Nobel Prize for Chemistry in 1945.

As a chemistry instructor at the University of Helsinki (1924–39), where he became professor of biochemistry (1939–48), Virtanen studied the fermentation processes that spoil stores of silage. Knowing that the fermentation product, lactic acid, increases the acidity of the silage to a point at which destructive fermentation ceases, he developed a procedure (known by his initials, AIV) for adding dilute hydrochloric or sulfuric acid to newly stored silage, thereby increasing the acidity of the fodder beyond that point. In a series of experiments (1928–29), he showed that acid treatment has no adverse effect on the nutritive value and edibility of the fodder and of products derived from animals fed the fodder.

Virtanen was also a professor of biochemistry at the Helsinki University of Technology (1931–39) and director of Finland’s Biochemical Research Institute, Helsinki, from 1931. He did valuable research on the nitrogen-fixing bacteria in the root nodules of leguminous plants, on improved methods of butter preservation, and on economical, partially synthetic cattle feeds. His AIV System as the Basis of Cattle Feeding appeared in 1943.

artturi-virtanen-1.jpg

#11 Re: Exercises » Compute the solution: » 2020-12-01 23:20:26

Hi,

Neat work!

820. Find the value of k if the expression

be a perfect square.

#12 Re: Ganesh's Puzzles » Coordinate Geometry » 2020-12-01 18:36:36

Hi,

Neat work!

CG # 133. Find the equation of the line passing through the points (-3, 2) and (4, 3).

#13 Re: Ganesh's Puzzles » Algebra » 2020-12-01 15:35:15

Hi,

Good work!

A # 102. For what value of k does the equation

has equal roots?

#14 Re: Ganesh's Puzzles » Oral puzzles » 2020-12-01 15:27:54

Hi,

Neat work!

#4873. Two numbers are in the ratio 4:5 and their Least Common Multiple is 180. Find the smaller number.

#15 Re: Ganesh's Puzzles » 10 second questions » 2020-12-01 15:17:29

Hi,

Well tried!

#7858. An article was sold for $5220 at a loss of 42% of the cost price. What will be the selling price of the article for a profit of 42%?

#16 Re: Ganesh's Puzzles » Mensuration » 2020-12-01 14:48:31

Hi,

Neat work!

M # 613. The base radius of a cone is two times the height. It is melted and recasted into cones of same height and radius half the height. How many cones can be mase?

#17 Re: Ganesh's Puzzles » Series and Progressions » 2020-12-01 14:40:47

Hi,

Excellent!

SP#621. The first term of an Arithmetic Progression is 6 and the sum of the first 6 terms is 66.
(a) What is the 6th term?
(b) What is the common difference of the Arithmetic Progression?
(c) What are the first 6 terms of this Arithmetic Progression?

#18 Re: Exercises » Compute the solution: » 2020-12-01 14:20:36

Hi,

819. Find the value of x for which the expression

has the greatest value.

#19 Jokes » More Rabbit Jokes - 4 » 2020-12-01 00:50:59

ganesh
Replies: 0

Q: What do you get when you find a rabbit with no hair?
A: A hairless hare!
* * *
Q: What would you call the Easter Bunny if he married a chicken?
A: The very first rabbit to lay an egg!
* * *
Q: What do you get when you pour hot water down a rabbit hole?
A: A hot cross bunny!
* * *
Q: What is white and has long ears, whiskers, and sixteen wheels?
A: Two rabbits on Rollerblades!
* * *
Q: What's the name of the rabbit who stole from the rich and gave to the poor?
A: Rabbit Hood.
* * *
Q: Where do rabbits work?
A: At IHOP restaurants!
* * *

#20 Re: Exercises » Compute the solution: » 2020-12-01 00:42:14

Good work!

818. When

is divided by (3x + 2), then find the remainder.

#21 Re: This is Cool » Miscellany » 2020-12-01 00:33:51

840) Kite

Kite, any of numerous birds of prey belonging to one of three subfamilies (Milvinae, Elaninae, Perninae) of the family Accipitridae. Typically, a kite is lightly built, with a small head, partly bare face, short beak, and long narrow wings and tail. Kites occur worldwide in warm regions. Some kites live on insects; others are primarily scavengers but also eat rodents and reptiles; and a few are strictly snaileaters. Kites are buoyant in flight, slowly flapping and gliding with wings angled back. Several species are as graceful as terns.

True kites, Milvinae, have rather narrow beaks, the upper mandible being wavy-edged. They are typified by the red kite (Milvus milvus)—of Europe, northern Africa, and the Middle East—and the black, or black-eared, kite (M. migrans)—found over much of the Old World. Both are large (to about 55 cm [22 inches]), reddish birds (the black kite darker), lightly streaked on the head, with long, angled wings and notched tail. The Brahminy kite (Haliastur indus; subfamily Milvinae) ranges from India to northeastern Australia. It is red-brown except for white foreparts. It eats fish and garbage. The buzzard kite (Hamirostra melanosternon; subfamily Milvinae) of Australia is a large black-breasted bird; it lives mainly on rabbits and lizards. It also eats emu eggs, reportedly dropping rocks on them to break the thick shells.

The snail kites, found only in the New World, also belong to the subfamily Milvinae. They have sickle-shaped beaks adapted to feeding on snails, their only food. Best known is the Everglade kite (Rostrhamus sociabilis), now rare in Florida and Cuba but occurring in numbers in eastern Mexico, Central America, and most of eastern South America. It is a blackish or slate-coloured bird, about 50 cm long, with red eyes and white tail-base.

The swallow-tailed kite of the New World (Elanoides forficatus) is a striking black and white bird of the subfamily Perninae. It is about 60 cm long, including its long forked tail. It is most common in tropical eastern South America but also occurs from Central America to the United States.

The swallow-tailed kite of Africa (Chelicti- nia riocourii) is a small gray and white bird of the subfamily Elaninae. It occurs from Nigeria to Somalia. The white-tailed kite (Elanus leucurus; subfamily Elaninae) occurs from Argentina to California, where it is one of the few North American raptors increasing in number. It is gray with a white tail, head, and underparts and conspicuous black shoulder patches. It eats rodents. Similar kites of the genus Elanus occur in tropical Africa, Asia, and Australia.

red-kite.jpg

#22 Re: Ganesh's Puzzles » Doc, Doc! » 2020-12-01 00:23:19

Hi,

#1557. What does the medical term 'Postpartum bleeding' or 'postpartum hemorrhage (PPH)' signify?

#23 Re: Ganesh's Puzzles » General Quiz » 2020-12-01 00:13:10

Hi,

#7713. Name the British ecologist sometimes described as the "father of modern ecology" ( (January 30, 1903 – May 17, 1991). He contributed for more than sixty years to the fields of limnology, systems ecology, radiation ecology, entomology, genetics, biogeochemistry, a mathematical theory of population growth, art history, philosophy, religion, and anthropology.

#7714. Name the German Humanist scholar, mineralogist and metallurgist  (24 March 1494 – 21 November 1555). Born in the small town of Glauchau, in the Electorate of Saxony of the Holy Roman Empire, he was broadly educated, but took a particular interest in the mining and refining of metals.

#24 Re: Ganesh's Puzzles » Oral puzzles » 2020-12-01 00:09:16

Hi,

#4872. Two numbers are in the ratio 3 : 5. If 5 is subtracted from each number, the new numbers are in the ratio 1 : 2. Find the sum of the numbers.

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