Answer:
Follows are the solution to the given points:
Explanation:
The value is attached in the image file please find it.
In point a:
First, we calculate the find the mean,
Formula:


To calculate the standard deviation, subtract the mean value from all observations then square its value:


please find attached file
In point b:
New

Calculate new mean:


calculating the standard deviation:


please find attached file
In point C:
Calculate new mean:


calculating the standard deviation:


please find attached file
In point d:
for b,
New

New

for c,
New

New
