<h2>
Answer:</h2>
The answer is 25 minutes
<h2>
Step-by-step explanation:</h2>
As we see the median time given in minutes before the installation was 53 minutes and after the installation it became 28 so by taking the difference which is 53 - 28 gives us 25 minutes.
Answer:
The value is 
Step-by-step explanation:
From the question we are told that
The sample size is n = 20
The sample mean is 
The standard deviation is 
Generally the standard error of the mean is mathematically represented as

=> 
=> 
Moving 4 units to the left would change from y=x^2 to y=(x+4)^2.