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When do you use the subjunctive?

The subjunctive is most commonly used in expressions of doubt ("dudo que + subj", "no creo que + subj") and the negative and formal imperative ("no hagas eso!", "por favor,...
RC
Answered by Raúl C. • Spanish tutor
2793 Views

Adam buys 4kg of sweets and pays £10 for them. Adam puts all of the sweers into bags with 250g in each bag. He sells the bags for 70p each. All the bags of sweets are sold, what is the percentage profit?

First you would figure out how many bags of sweets Adam made, this would be done by converting 4kg into grams (x1000) so 4 x 1000 = 4000g. Then you would divide the 4000g by 250g to see that 16 bags of sweet...
AS
Answered by Anton S. • Maths tutor
4022 Views

Using a suitable substitution, or otherwise, find the integral of [x/((7+2*(x^2))^2)].

The point of using a substitution when dealing with integrals is to reduce the problem from a very complicated integral to a simplistic one. How can we achieve this with our integral? Well, we know that when...
GF
Answered by George F. • Maths tutor
4973 Views

Describe and explain how the lungs are adapted to allow rapid exchange of oxygen between the air in the alveoli and blood in the capillaries around them. (5 marks)

The lungs have million of alveoli which increases the surface area , therefore increasing the rate of diffusion of oxygen into the lungs. The alveoli are very thin walled , which reduces the diffusion pathwa...
AZ
Answered by Aysha Z. • Biology tutor
13926 Views

How would you calculate the total blood volume of the body, without exsanguination?

Inject a solution of known volume into the blood. Allow this to circulate for an appropriate length of time, e.g. 5-10 mins, then take a blood sample. The dilution of the initial solution can then be calcula...
CF
1896 Views