the answer is B. 50% because half of adults only workout and the other adults don't workout
According to the research, the p wave on an electrocardiogram (ecg) represents the first wave of the cardiac cycle which is the atrial electrical depolarization.
<h3>What is an electrocardiogram?</h3>
It is the graph that records the electrical activity of the heart and allows the diagnosis of different cardiovascular diseases and helps to know the state of the heart muscle.
It presents a P wave (corresponding to atrial depolarization), a QRS complex (ventricular depolarization), and a T wave (ventricular repolarization).
Therefore, we can conclude that according to the research, the p wave on an electrocardiogram (ecg) represents the first wave of the cardiac cycle which is the atrial electrical depolarization.
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An infant's length will increase by 50 percent in the first year.
Hence option (d) is correct.
Infants grow about 25 cm throughout the first year, and height at age 5 is roughly twice the length at birth.
In general, length in normal-term infants increases by about 30% by 5 months and by > 50 percent by 12 months or 1 year.
Weight: An average of 13 ounces are gained every month, with the birthweight being doubled at around 4 to 5 months and tripled at one year.
Height: Most infants grow 10 inches in their first year, with an average monthly growth of slightly over 1/2 inch.
Hence, an infant's length will increase by 50 percent in the first year.
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