Ravi starts for his school from his house on his cycle at 8:20 a.m. If he runs his cycle at a speed of 10 km/h, he reaches his school 8 minutes late, and if he drives the cycle at a speed of 16 km/h, he reaches his school 10 minutes early. The school starts at:
1
8:40 a.m.
2
9:40 a.m.
3
8:50 a.m.
4
9:00 a.m.