Give a reasons why accumulation of lactic acid during vigorous
exercise leads to an increcise in heartbeat​

Lactic acid buildup when you’re exercising causes a build up of oxygen. Your body cannot break down glucose in the blood. So, your heart beat increases because there is more oxygen than normal needing to be pumped throughout the body.

In short terms: because your heart needs to pump more oxygen, it is pumping faster causing a faster heart rate.

lol , ok so the strength and the shacking of the earthquake diminishes with increasing distance from the earthquake's source, so the strength of shaking at the surface from an earthquake that occurs at 500km deep is considerably less than if the same earthquake had occurred at 20 km depth.

Explanation:

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