Solve the Problem $$H ( x ) = 70 - 4.9 x ^ { 2 }$$

Multiple Choice

Solve the problem.
-If a rock falls from a height of 70 meters on Earth, the height H (in meters) after x seconds is approximately $$H ( x ) = 70 - 4.9 x ^ { 2 }$$ When does the rock strike the ground? Round to the nearest hundredth, if necessary.

A) 14.29 sec
B) 2.92 sec
C) 3.78 sec
D) 1.71 sec