Activity 30

Carry out the following calculations, without your calculator.

• (a) 3 Ã— (60 + 70).

• (b) (3 Ã— 60) + 70.

• (c) (70 âˆ’ 60) Ã· 5.

• Author(s): The Open University

There are two very famous formulas for circles:

circumference of a circleÂ =Â Author(s): The Open University

You may like to add the area formulas in this section to your notes for future reference.

The simplest areas to find are those of rectangles. The area of a rectangle is its length multiplied by its breadth. Sometimes the dimensions of a rectangle are referred to as the base and the height, instead of the length and the breadth. The area is then expressed as the base multiplied by the height.

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Author(s): The Open University

A fundamental concept in mathematics is that of a function.

Consider, for example, the function f defined by

This is an example of a real function, because it associates with a given real number
Author(s): The Open University

School mathematics curricula often focus on lists of content objectives in areas like number, arithmetic, statistics, measurement, geometry, trigonometry, and algebra. A typical list of content objectives might contain over one hundred objectives to be introduced or revisited and learned each year. These can be seen as hierarchical in nature but many textbooks do not attempt to organise the objectives in ways that enable the bigger underpinning ideas to become apparent to the pupils. In addit
Author(s): The Open University

The environmental impact of teaching and learning
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Migration
Migration is a free course looking at the migrations of animals, with special reference to birds, and also introducing the themes of movement, selection and homeostasis. First published on Thu, 07 Sep 2017 as Migration. To find out more visit The Open University's Author(s): Creator not set

The frozen planet
This free course is a general introduction to the frozen planet, including the temperature in the polar regions; the energy from the Sun and the seasons; reading and understanding graphs and maps; and how the Arctic and Antarctic regions are defined. First published on Thu, 23 May 2019 as Author(s): Creator not set

Changing cities
Urban processes are increasingly held to be responsible for causing a variety of problems environmental destruction, social injustice, global financial instability. They are also identified as harbouring the potential to meet these challenges through urban experiments in sustainable living, creative culture and alternative economies. This free course, Changing cities, explores how contemporary processes of urbanisation challenge how we think about political agency, providing a framework for the
Author(s): Creator not set

The IPCC comparison between modelled and observed temperatures since the year 1860 is shown in the three charts below

Climate change is a natural process of warming and cooling that has occurred all through the Earth's history. Throughout geological time there have been â€˜hot-houseâ€™ periods and ice ages. In order to understand the current situation, it is necessary to have some sense of context and perspective, from historical and geological time-scales. The document below shows a chart showing a generalised temperature history of the Earth.

Click on the link below to see the chart

Author(s): The Open University

We are also guilty of importing exotic species, some of which, like the rhododendron (imported from Asia to Europe), have run riot in the absence of natural predators or primary consumers, and so have tended to out-compete native plants. Sometimes introductions have been accidental; rats and many disease-causing organisms have spread around the world via relatively modern transportation such as sailing ships. However, deliberate introductions, such as the rhododendron, have been made with wor
Author(s): The Open University

The lack of expertise in the developing countries shows up at a subsequent stage as well. One of the undoubted plus points of the WTO, compared with its predecessor the GATT, is its streamlined mechanism for settling disputes between members â€“ on the whole quite impartially. But although many of the larger developing countries have won cases against the most powerful members like the EU and USA, the smaller ones are hamstrung by their inability to field lawyers specialised in international
Author(s): The Open University

The Ministerial Declaration adopted by WTO members at Doha on 14 November 2001 fails to address the most pressing needs either of the poorest countries or of the world's most vulnerable communities. This means that the people who most need a share in global prosperity are still those least likely to obtain it.

(A joint statement by Actionaid, CAFOD, Christian Aid, Oxfam, Save the Children and five other charities a
Author(s): The Open University

Energy policy and climate change
The 2009 United Nations Climate Change Conference in Copenhagen presents a new focus for international debate and decisions about energy and its use. What are the countries of Western Europe and Scandinavia doing to promote sustainable energy production? Just how different will the future energy map of Europe look? And is energy policy principally a scientific issue or a political one? This album contains a series of films exploring energy policy in various countries around Europe in 2006, frame
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Structural Integrity: Materials Testing
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Do you think about where your water comes from? In the UK each of us uses an average of about 150 litres of water per day! The seven video tracks in this album consider issues of demand and quality in water supply as well as treatment processes. They give information on methods of minimising waste, emergency water treatment and effluent control. This material forms part of T308 Environmental monitoring, modelling and control.Author(s): The OpenLearn team

Waste Management
How much do you think about what you throw away? A waste management cycle is essential for a sustainable future. This album considers the policy and legislation that is driving waste management processes across the EU. By modelling the overall environmental impacts of solid waste disposal methods, the UK government has now created a hierarchy of waste and local management strategies. The 12 video tracks in this album offer an in depth look at each of these processes, concentrating on waste coll
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Noise Pollution
How do your ears work and what kind of sound levels can damage your hearing? The five video tracks in this album explain basic concepts such as units of noise, sound insulation and noise control. Car manufacturers like Lexus have developed the quiet car, but this kind of technology benefits the driver, not the people living beside busy roads. Locals from a Derbyshire village explain how the construction of the A50 has affected their lives. The Transport Research Laboratory analyses tyre noise on
Author(s): The OpenLearn team