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How do I know when to use the imperfect tense of the preterite tense?

Both the imperfect tense and the preterite tense are used to describe the past. However, they are used to describe different things. The imperfect tense is used to describe actions that happened repeatedly a...
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Answered by Bryony B. • Spanish tutor
3415 Views

2.11g of MgCl2 is added to 30cm3 of water. Find the concentration of chloride ions in the solution.

M r of MgCl 2 = 24.3 + 2(35.5) = 95.3 Moles added = 2.11/95.3 = 0.02214 Mol of cl - added = 2 0.02214 = 0.04428 Conc = 0.04428/(30 10 -3 ) = 1.48 moldm -3
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Answered by James S. • Chemistry tutor
3248 Views

How does blood flow through the heart?

The heart is the muscle responsible for pumping blood around the body. It has four chambers: an atrium and ventricle on the left, and an atrium and ventricle on the right. Atrioventricular and semilunar valv...
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Answered by Moriom B. • Biology tutor
12227 Views

Give one advantage and one disadvantage of laboratory experiments.

A question like this is likely to be worth 2-4 marks. In order to answer the question fully, you will need to state the advantage or disadvantage and then explain your reasoning. An advantage of laboratory e...
RD
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Use the binomial series to find the expansion of 1/(2+5x)^3 in ascending powers of x up to x^3 (|x|<2/5)

We want to rearrange the expression to the form (1+y)^n so we can use the general result: (1+y)^n=1+ny+[n(n-1)/2]y^2+[n(n-1)(n-2)/3!]y^3+... 1/(2+5x)^3 = (2+5x)^-3 = [2(1+5x/2)]^-3 = (2^-3)(1+5x/2)^-3 using ...
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Answered by Saskia J. • Maths tutor
14840 Views