Answer: 34 degrees of freedom should be used to find the p-value of the test .
Explanation:
Degrees of Freedom relates to the maximum number of independent values, that have independence to vary in the sample.
Given : When testing the difference between two population means and the population variances are unknown and unequal, the degrees of freedom are calculated as 34.7.
But degree of freedom must be an integer , so we find the greatest integer less than equal to the calculated degree of freedom.
i.e. [df]=[34.7]= 34
Thus , 34 degrees of freedom should be used to find the p-value of the test .