Live practice

Less haemoglobin means less oxygen can be transported from lungs to tissues. Aerobic respiration and ATP production fall, causing tiredness, weakness, breathlessness, dizziness and pallor; heart and breathing rates may increase to compensate. This condition is anaemia.

Copper is below hydrogen in the reactivity series and does not react with hot water or steam. Iron in steel can react with steam at high temperature and is also more liable to corrosion:

Copper is also a good conductor of heat, so it is suitable for the tank.

(a) Baking soda is mildly basic. It raises the milk's pH slightly above its natural value, delaying souring and preventing an immediate fall into the acidic range.

(b) Curd forms after sufficient lactic acid accumulates. Some of that acid must first neutralise the added baking soda. More time is therefore required for the pH to fall to the value at which milk proteins coagulate.

Define the sample space and count each favourable outcome once.

The final value lies in [0,1]; complement pairs also sum to one, providing an independent check.

Simplify the expression before substitution and preserve one-sided information.

Substitution into the original expression verifies the stated domain and final value.

Translate every condition into an equation and retain exact values throughout the ellipse calculation.

The last line satisfies the original conditions and supplies every requested part.

Translate every condition into an equation and retain exact values throughout the straight-line calculation.

The last line satisfies the original conditions and supplies every requested part.

Use the sequence definition or geometric-progression formula, keeping the first-term offset explicit.

The displayed substitutions cover every requested part and verify the result against the original data.

Proceed from the given expression and keep every transformation explicit.

The last line satisfies the required domain and establishes the result.

Proceed from the given expression and keep every transformation explicit.

The last line satisfies the required domain and establishes the result.