Q. A stone is dropped into a deep shaft without any initial velocity. The sound of the stone hitting the bottom is heard after 4 seconds. If the velocity of sound is 330 m/sec the depth of the shaft will be

• (A) 33.1 m
• (B) 2?2/3 m/s2
• (C) ?2/s m/s2
• (D) 4?2/9 m/s2