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Portfolio: what are your predictions for the future? use ideas from ex.1 as well as your own to write a short text similar to the ones on p. 46.you can draw pictures напишите 3-4 предложения про 2080 год.

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Ответ:
Luky4anovadasha
Luky4anovadasha
07.06.2020 08:09

Plastics are non-metallic, synthetic, carbon-based materials. They can be moulded, shaped, or extruded into flexible sheets, films, or fibres. Plastics are synthetic polymers. Polymers consist of long-chain molecules made of large numbers of identical small molecules (monomers). The chemical nature of a plastic is defined by the monomer (repeating unit) that makes up the chain of the polymer. Polyethene is a polyolefin; its monomer unit is ethene (formerly called ethylene). Other categories are acrylics (such as polymethylmethacrylate), styrenes (such as polystyrene), vinys (such as polyvinyl chloride (PVC)), polyesters, polyurethanes, polyamides (such as nylons), polyethers, acetals, phenolics, cellulosics, and amino resins. The molecules can be either natural — like cellulose, wax, and natural rubber — or synthetic — in polyethene and nylon. In co-polymers, more than one monomer is used.The giant molecules of which polymers consist may be linear, branched, or cross-linked, depending on the plastic. Linear and branched molecules are thermoplastic (soften when heated), whereas cross-linked molecules are thermosetting (harden when heated).Most plastics are synthesized from organic chemicals or from natural gas or coal. Plastics are light-weight compared to metals and are good electrical insulators. The best insulators now are epoxy resins and teflon. Teflon or polytetrafluoroethene (PTFE) was first made in 1938 and was produced commercially in 1950.Plastics can be classified into several broad types.1. Thermoplastics soften on heating, then harden again when cooled. Thermoplastic molecules are also coiled and because of this they are flexible and easily stretched.Typical example of thermoplastics is polystyrene. Polystyrene resins are characterized by high resistance to chemical and mechanical stresses at low temperatures and by very low absorption of water. These properties make the polystyrenes especially suitable for radio-frequency insulation and for parts used at low temperatures in refrigerators and in airplanes. PET (polyethene terephthalate) is a transparent thermoplastic used for soft-drinks bottles. Thermoplastics are also viscoelastic, that is, they flow (creep) under stress. Examples are polythene, polystyrene andPVC.2. Thermosetting plastics (thermosets) do not soften when heated, and with strong heating they decompose. In most thermosets final cross-linking, which fixes the molecules, takes place after the plastic has already been formed.Thermosetting plastics have a higher density than thermoplastics. They are less flexible, more difficult to stretch, and are less subjected to creep. Examples of thermosetting plastics include urea-formaldehyde or polyurethane and epoxy resins, most polyesters, and phenolic polymers such as phenol-formaldehyde resin.3. Elastomers are similar to thermoplastics but have sufficient cross-linking between molecules to prevent stretching and creep.

Объяснение:

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Ответ:
nastabugrim
nastabugrim
07.08.2020 04:00
The school I would like would have a swimming pool.

I'd have one for the first and second years and also for the third and fourth years. The playgrounds would be separate, one for the young children and the other for the senior forms. A wall would be separating them and there would be a door from one playground to the other.

The classrooms would have carpets instead of lino. The desks would be painted and the chairs would have cushions. The chairs would also be painted.

There would be a computer for every table in the classroom. There would be at least 12 videos for each classroom. The hall would be very big, about 40 metres long and 30 metres wide.

The lessons would be interesting. There would be lots of French and German and English.

There would be four floors at the school. There would be a lift to take us up. The staffroom would be much bigger than the one we have now.

It would be light and cosy. There would also be a big library. There would be a lot of instruments: flutes, guitars, drums, etc.

The school meals would have different food every day. There would be lots of visits to concerts and parks.

The tests would be easier for children.

Перевод:В школе, которая бы мне понравилась, был бы плавательный бассейн.

Я бы занимался там в первый и второй годы обучения, а также в третьем и четвертом классах. Площадки были бы отдельными: одна — для младших школьников, а другая — для старшеклассников. Их бы разделяла стена с дверью.

В классных комнатах вместо линолеума лежали бы ковры. Парты были бы разукрашены, а на стульях были бы подушки. Стулья тоже были бы разукрашенными.

На каждом столе был бы компьютер. В каждой классной комнате было бы, по меньшей мере, двенадцать видеомагнитофонов. Коридор был бы очень большой: около 40 м в длину и 30 м в ширину.

Уроки были бы интересными. Проводилось бы много уроков французского, немецкого и английского.

Школа была бы четырехэтажной. В ней был бы лифт, чтобы подниматься вверх. Учительская была бы намного больше, чем сейчас.

Она была бы светлой и уютной. В школе была бы большая библиотека, много музыкальных инструментов: флейты, гитары, барабаны и т. д.

Питание в школе было бы разнообразным. Организовывались бы посещения концертов, парков.
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