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Explain the ontological argument

Our concept of God is that of a being greater than which none can be imagined. Since we are able to imagine God at all, then we can see the God exists as an idea in the mind. However, it seems that a thing w...
HC
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How should I structure my History essays?

Every history essay aims to answer a question. You may be asked to evaluate the importance of one factor, or to balance the importance of many, in an historical event. Sometimes you may be asked to ‘discuss’...
CU
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How do you calculate the sine, cosine and tangent values for 45 degrees without a calculator?

To find the values for 45 degrees, we construct a right angled isosceles triangle, which has two sides of equal length. We can say that these sides are 1 unit long, and so we can figure out the value of the ...
HC
Answered by Heather C. Maths tutor
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Tritium is a radioactive nucleide with a half life of 4500 days, determine the time for 90% of it to decay.

We know that the number of undecayed nuclei, N, is given by N=N 0 e -lambda t . From this, by setting N=N 0 /2 we know at this point that t= T 0.5 (the half life) and can show that lambda =ln(2)/T 0.5 . Henc...
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Answered by Luke C. Physics tutor
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I decrease a number by 26%, the answer is 9 x10^-7, what was the original number?

The number has been decreased by 26%, this means that the original number is 100-26=74% of the original value. Therefore 9 x 10 -7 = 0.74 x N, where N is the original number. Hence N=(9 x 10 -7 )/0.74 = 1.21...
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Answered by Luke C. Maths tutor
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