Answer:
B) Add appropriate quantities of weak acid and its conjugate base to water.
C) Partially neutralize a weak acid solution by addition of a strong base.
(D) Partially neutralize a weak base solution by addition of a strong acid.
Explanation:
A buffer solution is made by a weak acid and its conjugated base or a weak base and its conjugated acid.
If you add a weak acid to water, you can adjust the pH of the buffer solution by adding a strong base.
If ypu add a weak base to water, you can adjust the pH of the buffer solution by adding a strong acid.
Answer: 
Explanation:
Given : Sample size : n= 30 , it means it is a large sample (n≥ 30), so we use z-test .
Significance level : 
Critical value: 
Sample mean : 
Standard deviation : 
The formula to find the confidence interval is given by :-
i.e. 
i.e. 
Hence, the 95% confidence interval for the mean mpg in the entire population of that car model =
You multiply the number of atoms by 12 to get how many electrons (since each atom has 12 electrons in it)
you multiply the number of atoms by 13 to get how many neutrons
(since each atom of this isotope has 13 neutrons in it)
