Answer: b. 8.56 to 21.44
Step-by-step explanation:
Let
be the mean number of pushups that can be done.
As per given , we have
Sample size : n= 10
Degree of freedom = n-1=9
Sample mean : 
Sample standard deviation : 
Significance level : α=1-0.95=0.05
From t- distribution table ,
Critical two -tailed t-value for α=0.05 and df = 9 is

Confidence interval for
is given by :-


Hence, the 95% confidence interval for the true mean number of pushups that can be done is 8.56 to 21.44.
The closing price on Thursday was $25.69 and on Wednesday, it went down by 0.75. and it went down again by 0.75 which brought it to $25.69.
That would mean the closing price on Wednesday was $26.44 (25.69 + 0.75)
I think a but not sure but i hope i helped :D