Answer:
 and
 and 

The null hypothesis is not rejected
Step-by-step explanation:
Given
Random sample of 50 commuter times
Solving (a): The null and alternate hypothesis
From the question, a previous census shows that:
 and
 and 
This is the null hypothesis i.e.

Reading further, a new test was to show whether the average has decreased.
This is the alternate hypothesis, and it is represented as:

Solving (b) and (c): The test statistic (T).
This is calculated using:

In this case:
 
    and
 and 
So:




Solving (c): Accept or reject null hypothesis

First calculate the degrees of freedom (df)


From the t distribution table, 
At:  ,
,   and
 and 
the t score is:


<em>So, the null hypothesis is not rejected</em>