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Explain how you would test for the presence of lipids and proteins in an unknown solution. Give details on any observations you would expect to make.

To test for the presence of lipids, you would carry out the emulsion test. To do this, you take the sample and mix it with equal volumes of ethanol and water followed by shaking. A cloudy white emulsion w...

Answered by Chelsea J. • Biology tutor

63329 Views

Why is the derivative of sin(x), cos(x)?

Find out what they know what the questions means, ie if they know what sinx and cosx are and then how much they understand about what derivatives are.I would explain from the point they're at, define ever...

Answered by Ryan A. • Maths tutor

3604 Views

f(x) = x^3 + 3x^2 + 5. Find (a) f ′′(x), (b) ∫f(x)dx.

(a) To find the second derivative of f(x) we must differentiate f twice.the first derivative of f is f'(x)= 3x^2 + 6xthe second derivative therefore is f''(x)= 6x +6
(b) The integral of f(x) with res...

Answered by Samraj C. • Maths tutor

7930 Views

Given an ordered array of integers "V" and a integer "Sum", write a function that would return "true" if it finds two numbers in V that add up to Sum, and "false" otherwise.

Because there is no unique solution to the problem the goal is to think different ways to approach an issue and ultimately opt for the best one in terms of complexity. There is an example of set of answer...

Answered by Fabio D. • Computing tutor

1657 Views

Explain why Xenon had a lower first ionisation enthalpy than Neon. (3 marks)

Xenon is further down Group 8 of the Periodic Table than Neon, hence has its outermost electrons in higher energy shells further away from the nucleus. Therefore, there are more full inte...

Answered by Alex M. • Chemistry tutor

10343 Views