Answer:
4.3cm
Step-by-step explanation:
the radius of the hemisphere can be determined its volume
volume of a hemisphere = (2/3) x (n) x (r^3)
n = 22/7
r = radius
(2/3) x (22/7) x( r^3) = 165 cm^3
44/21 x r^3 = 165
divide both sides of the equation by 21/44
165 x 21/44
r^3 = 78.75
find the cube root
r = 4.2863 cm
the tenth is the first number after the decimal place. To convert to the nearest tenth, look at the number after the tenth (the hundredth). If the number is greater or equal to 5, add 1 to the tenth figure. If this is not the case, add zero
the 100th terms, 8 is greater than 6, so add 1 to 2. this give 4.3cm
Answer:
The 99% confidence interval for the fraction of US adult Twitter users who get some news on Twitter is (0.4872, 0.6018). It means that we are 99% sure that the true proportion of US adult Twitter users who get some news on Twitter is between 0.4872 and 0.6018.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
, and s is the standard error.
54% of US adult Twitter users get at least some news on Twitter.
This means that 
The standard error for this estimate was 2.4%
This means that 
99% confidence level
So
, z is the value of Z that has a pvalue of
, so 
The lower bound is:

The upper bound is:

The 99% confidence interval for the fraction of US adult Twitter users who get some news on Twitter is (0.4872, 0.6018). It means that we are 99% sure that the true proportion of US adult Twitter users who get some news on Twitter is between 0.4872 and 0.6018.