to measure heart rate one could use an electrocardiogram
the human body is mainly salty water and so it conducts electrisity. the electrical activiy which spreads across the heart aslo spreads outwards away from the heart. this causes the voltage of the skin to change slightly. these potential differences can be detected by a electrocardiogram at various parts of the body
The pulse (usually taken in the wrist) measures the heart rate.
A rate is a ratio which measures a certain variable in an amount of time. The most common rate would be distance / time (which measures speed).
how the annual percentage rate measures the true cost of a loan
frequency
The measure is the rate of reaction.
A heart-rate monitor is used.
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Labour rate variance .
the percent of a population living in an urban area.
rate of change of velocity with respect to time.
An atmometer is an instrument which measures the rate of evaporation of a liquid.
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