Answer:
The conclusion is that the researcher was correct
Step-by-step explanation:
From the question we are told that
The sample size is 
The sample mean is 
The standard deviation is 
The significance level is 
The Null Hypothesis is 
The Alternative Hypothesis is 
The test statistic is mathematically represented as

Substituting values


Now the critical value for
is

This obtained from the critical value table
So comparing the critical value of alpha and the test value we see that the test value is less than the critical value so the Null Hypothesis is rejected
The conclusion is that the researcher was correct