The right answer is to measure the amount of released carbon dioxide.
The carbon dioxide exhaled by the lungs can reflect the energy consumed by the body since it comes from the degradation of glucose which is the main energy substrate. And this is a better indicator of energy consumption than measuring heart rate because it can be inflected by several factors.
A is false because glucose is not found in the urine, except in the case of diabetes mellitus.
C is false because the consumption of calories does not mean that we will directly use it.
D is wrong because perspiration is independent of energy consumption, this is a way to cool the body after exercise.
If lactic acid builds up in the body more quickly than it can be removed, acidity levels in bodily fluids — such as blood — spike. lactic acid buildup occurs when there's not enough oxygen in the muscles to break down glucose and glycogen.
The major organ of the circulatory system that causes blood to flow through the body by its pumping action is the heart.
Star brightness is defined by either <span>D. apparent magnitude - when we measure it from Earth (that is how bright it is from Earth) - this is the closest to "basic observation" and the best answer
or by absolute magnitute - how bright it would be at a certain distance (this allows to compare the brightness).
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