Answer:
The wavelength, of a sound wave with a frequency of 20 waves per second is 15,000,000 m.
Step-by-step explanation:
In this question, we have to calculate the wavelength of a sound wave of frequency 20 waves per second.
We know that the speed of light in air/ vacuum is .
Now by the formula v = nλ , where v = speed of light in air/vacuum, n = frequency of the wave and λ = wavelength in meters,
we put the values
= 20 × λ
λ =
λ = 15,000,000 m
Answer:
a
b
Ca
Cb
Explanation:
From the question we are told that
The sample size is n = 100
The upper limit of the 95% confidence interval is b = 47.2 years
The lower limit of the 95% confidence interval is a = 34.5 years
Generally the sample mean is mathematically represented as
=>
=>
Generally the margin of error is mathematically represented as
=>
=>
Considering question C a
From the question we are told the confidence level is 90% , hence the level of significance is
=>
The sample size is n = 22
Given that the sample size is not sufficient enough i.e we will make use of the student t distribution table
Generally the degree of freedom is mathematically represented as
=>
=>
Generally from the student t distribution table the critical value of at a degree of freedom of 21 is
Considering question C b
From the question we are told the confidence level is 80% , hence the level of significance is
=>
Generally from the normal distribution table the critical value of is