Gradual changes in the frequency of diseases over long periods are known as SECULAR TIME TRENDS. For example, the rate of mortality in USA due to coronary heart diseases over a period of time. Onset of puberty in girls is also a secular time trend.
Secular time trend is also referred as Secular Variation and Secular Drift.
Answer:
No
Explanation:
The reason why cause you are stupid
The immune system. It produces antibodies which fight the bacteria or virus that caused the infection
E) be more susceptible to disease and famine
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-Payshence
Answer: 0.04metres
Explanation:
The wavelength of a wave is the distance covered by the wave after one complete cycle. It is measured in metres, and represented by the symbol λ
Recall that Velocity (V) = Frequency F x wavelength λ
V = F λ
Make λ the subject formula
λ = V / F
In this case Frequency = 0.4 kHz
Convert kilohertz to hertz by multiplying 0.4 by 1000 i.e (0.4 x 1000Hz) = 400Hz
Velocity of wave = 16 m/s
So, λ = V / F
λ = 16 m/s / 400Hz
λ = 0.04metres
Thus, the wavelength of a wave is 0.04metres