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Describe the Darwinian theory of natural selection (GCSE/A-Level)

Every individual of every species living on the planet has DNA, made up of sections called genes. Mutations to these genes occur over time, resulting in a change to an individual's behaviour or physiology. T...
BD
Answered by Bill D. Biology tutor
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Prove that the square of an odd number is always 1 more than a multiple of 4. [Edexcel Higher Tier 2018, Paper 1: Question 12]

We want to start with “the square of an odd number” and show something. Remember that any odd number can be expressed as 2n+1 (an even number is 2n, and any odd number is 1 larger than an even). So squaring ...
RH
Answered by Robert H. Maths tutor
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How do i form the imperfect subjunctive tense?

First of all, it's important to remember that you wont be required to spontaneously conjugate verbs into the imperfect subjunctive at this level! You may have to identify them in texts, but you won't be aske...
LE
Answered by Lauren E. Spanish tutor
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What’s the difference between a eukaryote and a prokaryote?

A prokaryote will not contain membrane-bound organelles, whereas a eukaryotic cell will contain membrane-bound organelles.Examples of membrane bound organelles would be the nucleus, mitochondria and chloropl...
CM
Answered by Camilla M. Biology tutor
3318 Views

How do i solve the simultaneous equations 7x+y=1 and 2x^2-y=3?

First, label the equations 1 and 2:1: 7x+y=1 and 2: 2x^2-y=3Rearrange equation 2 in terms of yy=2x^2-3Now substitue the rearranged version of equation 2 into 1 to give7x+2x^2-3=1.Bring all the values to the ...
IN
Answered by Irida N. Maths tutor
3442 Views