List of top B.Ed Questions on Reasoning

If 'All Teachers are Mentors' and 'Some Mentors are Authors', is the conclusion 'All Teachers are Authors' definitely true?
A man walks 5 km South, turns left and walks 3 km, then turns left again and walks 5 km. In which direction is he from the starting point?
Find the missing number in the series: 3, 7, 15, 31, 63, __?