12 times breathe give 240 ml of pure 
. Each breathe gives 20 ml of .
Let us consider, volume of air per breathe= x ml.
Pure from inhaled air= 
ml and Pure from exhaled air= 
ml.
Pure from inhaled and exhaled air= 20 ml
So, + = 20
Therefore, x = 55.5 ml
So, volume of air per breath= 55.5 ml.
Blood.
<span>Blood is heterogeneous because it has corpuscles (blood cells and platelets) physically suspended in blood plasma. Blood plasma and the corpuscles have different properties and can be separated by methods such as centrifugation. Also, blood is considered a colloid suspension because it has the properties of both a colloid and a suspension. This is because the blood plasma acts as a colloid. More so, if blood was left to settle,then the blood cells would collect at the bottom hence taking the characteristic of a suspension. </span>
<span>Salad dressing.</span>
<span>Depending on the type of salad, it can either be a heterogeneous or homogeneous mixture. If the salad dressing is only of vinegar or any other oil, then it is a homogenous mixture. However, if it involves a mixture of vinegar and other oils, pepper, herbs, and etcetera, then it is a heterogeneous mixture</span>
Answer: Option (A) is the correct answer.
Explanation:
When energy is transferred from the air to the water then energy is absorbed by the water molecules.
This energy travels through one molecule of water to another molecule of water by the process of convection.
Thus, we can conclude that when energy is transferred from the air to the water, then it travels through the water.
