Choose the one alternative that best completes the statement or answers the question.
-An object is dropped from a bridge. A second object is thrown downwards 1.0 s later. They both reach the water 20 m below at the same instant. What was the initial speed of the second object?
Neglect air resistance.
A) 9.9 m/s
B) 4.9 m/s
C) 20 m/s
D) 21 m/s
E) 15 m/s