Answer:


The confidence interval of standard deviation is:
to 
Step-by-step explanation:
Given

See attachment for the formatted data
Solving (a): The mean
This is calculated as:

So, we have:




Solving (b): The standard deviation
This is calculated as:




--- approximated
Solving (c): 95% confidence interval of standard deviation
We have:

So:



Calculate the degree of freedom (df)



Determine the critical value at row
and columns
and 
So, we have:
---- at 
--- at 
So, the confidence interval of the standard deviation is:
to 
to 
to 
to 
Answer:
7x^2 -128x -19
Step-by-step explanation:
Answer:
Step-by-step explanation:
The line is passing through 2 points: (0,9 and (3,3)
slope=(9-3)/(0-3)=-2
equation is : y-9=-2(x-0) or y=-2x+9
Answer:
4.4
Step-by-step explanation:
The tenth place in this number is 4.<u>4</u>32, so that should be the last digit.
Now, we need to know wether to round up or down. That is determined by the digit that comes after it. <em>If that digit, here it is the hundredth, is 0-4, it rounds down, if it is 5-9, it rounds up</em>. Our next digit is <em>3</em>, which goes into the first category, <em>so the number rounds down</em>, so the tenth remains the same. That leaves us with 4.4.