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How does the process of eutrophication work?

As we know, fertilisers are used by farmers to increase crop yield, and artificial fertilisers in particular are very high in nutrients such as phosphorus and nitrogen which stimulate plant growth. Howeve...

Answered by Daisy H. • Biology tutor

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An arithmetic progression has a tenth term (a10) = 11.1 and a fiftieth term (a50) = 7.1 Find the first term (a) and the common difference (d). Also find the sum of the first fifty terms (Sn50) of the progression.

We start off by constructing simultaneous equations as there are two variables - a and d - that we do not know. We use the formula:a_n = a + (n-1)di) 11.1 = a + 9dii) 7.1 = a + 49d
i) - ii)...

Answered by • Maths tutor

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I have an infinite number of glass blocks stacked side by side. The first block has refractive index n1, the second n2 and so on, such that n1<n2...<n(infinity). I shine a light on the stack, what angle does the ray make to the normal on the last block?

This question tests your knowledge of the behaviour of light through different mediums. We know that when light travels from air through glass, it tends towards the normal. This is because the glass is de...

Answered by Alex C. • Physics tutor

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How far does the application of new technologies explain the economic boom of the 1920s?

New technologies as well as mass production were central in causing the economic boom of the 1920s. Conveyor belt and moving assembly lines allowed mass production to take place following the introduction...

Answered by • History tutor

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Outline the process of phagocytosis by macrophages.

Initially, the bacteria/pathogen will bind to a receptor located on the surface membrane of the macrophage. Pseudopodia will form around the bacteria, resulting in the macrophage surrounding the bacteria/...

Answered by • Biology tutor

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