Answer:a
a
b
The margin of error will increase
c
The margin of error will decreases
d
The 99% confidence interval is
Step-by-step explanation:
From the question we are told that
The sample size
The sample mean is
The standard deviation is
Given that the confidence level is 95% then the level of significance is mathematically represented as
Next we obtain the critical value of from the normal distribution table
So
The margin of error is mathematically represented as
=>
=>
The 95% confidence interval is
=>
=>
When the confidence level increases the also increases which increases the margin of error hence the confidence level becomes wider
Generally the sample size mathematically varies with margin of error as follows
So if the sample size increases the margin of error decrease
The sample proportion is mathematically represented as
Given that the confidence level is 0.99 the level of significance is
The critical value of from the normal distribution table is
Generally the margin of error is mathematically represented as
=>
=>
The 99% confidence interval is