Answer:
the answer to this question is b
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:
4:5
Step-by-step explanation:
since there are 4 oranges bought for every 5 apples, the ratio of oranges to apples sold is 4:5
Answer:
They both weigh the same amount.
Step-by-step explanation:
A pound of feathers would land and wouldn't hurt, but a pound of bricks would hurt.
Since they both are exactly one pound, if that is the only question and it's a one-part question then there's your answer.
4(-9*x)
Multiply the two numbers
-36x
Final answer: -36x