A stone was thrown vertically upwards from the ground with a velocity of 50 m/sec. After 5 seconds another stone was thrown vertically upwards from the same place. If both the stones strike the ground at the same time, then the velocity with which the second stone was thrown should be (Assume g = 10 m/sec²)

• A. 40 m/sec
• B. 50 m/sec
• C. 15 m/sec
• D. 25 m/sec

Answer: (D)