Final answer:
The velocity of a rock dropped from a height of 2.5 meters is found to be 7.0 m/s right before it hits the ground, using the formula v = √(2gh) with g = 9.80 m/s².
Step-by-step explanation:
When a rock is dropped from a height, its velocity can be determined using the equation v = √(2gh), where v is the final velocity, g is the acceleration due to gravity (approximately 9.8 m/s^2), and h is the height from which the rock is dropped. In this case, the rock is dropped from a height of 2.5 meters, so the velocity when it reaches the ground is v = √(2 * 9.8 * 2.5) = 7.0 m/s. Therefore, the correct answer is option A.