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Given that your grade for your computing is based on 5 coursework that weigh differently, and you know the results of 4: 80, 75, 50 and 90 which weighs 10%, 20%, 45% and 5%. What grade do you need in your last coursework to achieve at least a B (70%)?

You know the following: A) 80, 10% B) 75, 20% C) 50, 45% D) 90, 5% E) X, (100-10-20-45-5)% = 20% Therefore, create a formula with the facts given and the mean marks must be at least 70. Note that 10% is equi...
CZ
Answered by Chen Z. • Maths tutor
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What is a proposed model for enzyme activity?

The lock and key model: Only substrates of a specific shape that is complementary to the active site of an enzyme can fit into the active site, in a way that is analagous to a key fitting into a lock.
AP
Answered by Alastair P. • Biology tutor
5263 Views

How is the structure of alveoli suitably adapted for efficient gas exchange?

Very thin walls result in a short diffusion distance which makes gas exchange particularly favourable. Lots of branches and sacs result in a large surface area so gas exchange can be maximised.
AP
Answered by Alastair P. • Biology tutor
7972 Views

What are the differences between exons and introns found in DNA.

Exons are coding regions of DNA, and are copied into mRNA and transcribed as proteins. Introns are non-coding regions of DNA, and are spliced out of pre-mRNA so are not copied into mRNA.
AP
Answered by Alastair P. • Biology tutor
11654 Views

Explain what a hydrocarbon is, and suggest two properties of hydrocarbons that leave a fractioning column near the top.

A hydrocarbon is a molecule that contains only hydrogen and carbon atoms. Any two of the follwing properties are suitable answers: Low boiling points, low viscosities or high flammability.
AP
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