1. How far does student walk:- option 2
sol; 1 km before bus stop and 1 km after bus stop to university= 2 km
2. How far is he from university student's union at 8.20 am? option 3
sol: at 8:20 student has covered 3 km and university is 6 km far from start point .So 6-3= 3 km
3. What is the average speed of the bus? option 2
sol: bus starts at 8:15 to 8:25 (10 minutes) and covers 4 km
average speed = distance/time= 4km/10 min= 24 KMPH