Answer:

We can use the p value as a decision rule is
we reject the null hypothesis.
Now we can find the degrees of freedom given by:

And the p value would be:

And since the
we have enough evidence to reject the null hypothesis in favor to the alternative hypothesis.
Step-by-step explanation:
For this case we have the following statistics for the difference between the paired observations:
the sample mean for the paired difference
the sample deviation for the paired difference data
the sample size
The system of hypothesis that we want to check is:
Null hypothesis: 
Alternative hypothesis: 
And the statistic is given by:

And replacing we got:

We can use the p value as a decision rule is
we reject the null hypothesis.
Now we can find the degrees of freedom given by:

And the p value would be:

And since the
we have enough evidence to reject the null hypothesis in favor to the alternative hypothesis.