An electronic calculator is a small, portable electronic device used to perform both arithmetic operations and complex mathematical operations.

The first solid electronic calculator was created in the 1960s, building on the extensive history of tools such as the abacus (developed around 2000 BC), and the mechanical calculator (developed in the 17^th century AD). It was developed in parallel with the analog computers of the day.

In addition to general purpose of calculators, there are those designed for specific markets, for example, there are scientific calculators which include trigonometric and statistical calculations. Some calculators even have the ability to do computer algebra. Graphing calculators can be used to graph functions defined on the real line, or higher dimensional Euclidean space.

What is the meaning of “extensive” in the second paragraph?

A laptop is a kind of computer unit which has the same function as a PC (Personal Computer), but it’s smaller, lighter and of different sizes. Nowadays, most people choose laptops for several reasons.

A laptop is a portable device. This portability is very helpful for our work, study and other activities. We do not need complicated cable installations to activate a laptop. With a laptop, we can do our work anytime and anywhere.

Moreover, a laptop allows us to access the internet in public places which provide free access called hot spot areas. Some people like to use this facility to carry out their tasks.

Finally, a laptop consumes energy more efficiently than a PC does. This device uses a rechargeable battery as a source of electric energy. So, if we prefer using a laptop, it means that we support the government program to save energy. That’s why a laptop has become very popular recently.

What is the purpose of the text above?

A camera is an optical instrument for recording images, which may be stored locally, transmitted to another location, or both. The images may be individual still photographs or sequences of images constituting videos or movies. The functioning of the camera is very similar to the functioning of the human eye.

A camera may work with the light of the visible spectrum or with other portions of the electromagnetic spectrum. A still camera is an optical device which creates a single image of an object or scene, and records it on an electronic sensor or photographic film. All cameras use the same basic design: light enters an enclosed box through a converging lens and an image is recorded on a light-sensitive medium.

A shutter mechanism controls the length of time that light can enter the camera. Most photographic cameras have functions that allow a person to view the scene to be recorded, allow for a desired part of the scene to be in focus, and to control the exposure so that it is not too bright or too dim.

A movie camera or a video camera operates similarly to a still camera, except it records a series of static images in rapid succession, commonly at a rate of 24 frames per second. When the images are combined and displayed in order, the illusion of motion is achieved.

The function of camera is described in paragraph …

A camera is an optical instrument for recording images, which may be stored locally, transmitted to another location, or both. The images may be individual still photographs or sequences of images constituting videos or movies. The functioning of the camera is very similar to the functioning of the human eye.

A camera may work with the light of the visible spectrum or with other portions of the electromagnetic spectrum. A still camera is an optical device which creates a single image of an object or scene, and records it on an electronic sensor or photographic film. All cameras use the same basic design: light enters an enclosed box through a converging lens and an image is recorded on a light-sensitive medium.

A shutter mechanism controls the length of time that light can enter the camera. Most photographic cameras have functions that allow a person to view the scene to be recorded, allow for a desired part of the scene to be in focus, and to control the exposure so that it is not too bright or too dim.

A movie camera or a video camera operates similarly to a still camera, except it records a series of static images in rapid succession, commonly at a rate of 24 frames per second. When the images are combined and displayed in order, the illusion of motion is achieved.

The word rapid in par.4 has similar meaning like…

Earthquake

Earthquake is a sudden shaking of the earth’s surface that often causes a lot of damage. It is the result of a sudden release of stored energy in the Earth’s crust that creates seismic waves. Earthquakes may happen naturally or as a result of human activities. Smaller earthquakes can also be caused by volcanic activity, landslides, mine, blasts, and nuclear experiments.

What is the purpose of the paragraph?

Coconut tree is a tree of the palm family. It is one of tree which live in tropical countries. Coconut tree is tall palm tree bearing coconut as fruit. Cocos nucifera is binomial name of its.

Coconut tree can grow up to 30m height. They have a single cylindrical trunk. At the top of the trunk there are pinnate leaves. They are about 3 to 4 m long and the pinnate 60 to 90 cm long. The fruit of coconut tree is coconut. It is oval and the diameter is about 30 cm long. It has thick husk and a hard shell. Inside the shell there is white meat and sweet liquid.

Based on the text, we can conclude that....

Earthquake is a sudden shaking of the earth’s surface that often causes a lot of damage. It is the result of a sudden release of stored energy in the Earth’s crust that creates seismic waves. Earthquakes may happen naturally or as a result of human activities. Smaller earthquakes can also be caused by volcanic activity, landslides, mine, blasts, and nuclear experiments.

What is an earthquake?

Why talking to dolphin is not easy?

For many years people believed that the cleverest animals after man were the chimpanzees. Now, however, there is a proof that dolphins may be even cleverer than these big apes.

Although a dolphin lives in the sea, it is not a fish. It is a mammal. It is in many ways, therefore, like a human being.

Dolphins have a simple language. They are able to talk to one another. It may be possible for man to learn how to talk to dolphins. But, this will not be easy because dolphins cannot hear the kind of sounds man can make. If man wants to talk to dolphins, therefore, he will have to make a third language which both he and the dolphins can understand.

Dolphins are also very friendly toward man. They often follow ships. There are many stories about dolphins guiding ships through difficult and dangerous waters.

Why talking to dolphin is not easy?

Butterflies ... insects. With their almost endless variety of colors, shapes, and sizes they are amongst the most and beautiful and easily recognized of insects.

All butterflies ... by drinking through a straw-like tube called proboscis which is coiled when not in use.

Which statement is the definition of factual report?

When people talk about “going on a diet”, they usually mean they are trying to limit the amount and type of food that they ..., in order to become thinner. Nevertheless, diet actually refers to sensible nutrition for a variety of purposes – to gain, as well as to (....) weight. A diet can also be ... as part of medicinal procedures, for example, to counteract summer heat or winter cold and treat someone who suffers from stomach troubles.

Milk

Milk is produced by female animals and women for feeding their babies.

Women produce milk for their babies, cows produce milk for their calves, mares for their foals, and so on. In fact, the young of mammals are fed solely on milk from birth – human babies up to three or four months old. Young mammals continue to feed on milk, even when they are introduced to solid food.

Milk provides the primary source of nutrition for newborn babies before they are able to digest solid food. It contains protein, fat, lactose and calcium as well as vitamins.

What do we call young cows?

Milk

Milk is produced by female animals and women for feeding their babies.

Women produce milk for their babies, cows produce milk for their calves, mares for their foals, and so on. In fact, the young of mammals are fed solely on milk from birth – human babies up to three or four months old. Young mammals continue to feed on milk, even when they are introduced to solid food.

Milk provides the primary source of nutrition for newborn babies before they are able to digest solid food. It contains protein, fat, lactose and calcium as well as vitamins.

Which paragraph indicate general classification?