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Describe how oxygen in the air reaches the capillaries surrounding the alveoli in the lungs.

Oxygen moves down the trachea, into the bronchi and into the smaller bronchioles, down a pressure gradient. Once the oxygen reaches the alveoli it moves down a diffusion gradient across the alveolar epith...

Answered by Sasha J. • Biology tutor

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State the meaning of the term first ionisation energy

Energy (or enthalpy) needed to remove one electron from one atom.

Answered by Azobir E. • Chemistry tutor

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Solve the simultaneous equations: x^2 + 8x + y^2; x - y = 10.

Label the two equations.

x² + 8x + y² = 84 (1)
x - y = 10 (2)

Rearrange (2) to get y = x - 10 and substitute for y in (1) to get x² + 8x + (x - 10)

Answered by Lewis T. • Maths tutor

5526 Views

To what extent can the judiciary protect individual rights and liberties?

In wake of the Brexit fallout, this question is particularly unclear at present, as changes to our relationship with the European courts reamin undecided. However, looking at just the national level there...

Answered by Sam K. • Politics tutor

3935 Views

What is the binomial theorem and why is it true?

The binomial theorem is an algebraic formula for the expansion of powers of an expression with two terms (a binomial). For example, we can use it to calculate the polynomial expansion of, say, (1+x)^n for...

Answered by Jacob C. • Maths tutor

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