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Why is the polymerase chain reaction important and how does it work?

The polymerase chain reaction (or PCR) is extremely useful at copying fragments of DNA so by the end of it you have a much bigger sample than what you started with. This is particularly useful for example, i...
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Answered by Benito W. • Biology tutor
10006 Views

How can I write an exam answer on an unseen text that I really don’t understand?

Having to analyse an unseen passage or poem in an exam can be very daunting and it’s often tempting to panic when you first see what you’ve been given. The most important thing to do, however, is to stay cal...
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16990 Views

Whats the difference between speed and velocity?

Although these two words can be used interchangably they are very very different. Its easier to explain if you break down their equatoins. Speed = distance / time Velocity = displacement / time The differenc...
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Answered by Michael G. • Physics tutor
9948 Views

Whats the difference between the three main trigonometric functions?

Sin(x), Cos(x) and Tan(x) are very useful functions and can be used to solve algerbraic problems where the aim is to find the size of an angle or a size. Sin(x) = Opposite/Hypotenuse Cos(x) = Adjacent/Hypote...
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Answered by Michael G. • Maths tutor
5281 Views

How do I answer an essay question in an exam?

Answering essay questions in exams can seem a daunting task, especially in a subject like History, but there really is no need to panic. History exams are all about preparation. There are three simple steps ...
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Answered by Jenni S. • History tutor
9883 Views