Final answer:
The speed of sound is calculated by dividing the total distance traveled by the sound (which is twice the distance to the building, 1020 meters) by the time taken (3 seconds), resulting in 340 meters per second. The correct option is B. 340 meters per second.
Step-by-step explanation:
To find the approximate speed of sound in the air based on the scenario where the student hears an echo after 3 seconds, we need to first understand that the sound has to travel to the building and back, making the total distance traveled twice the distance from the student to the building.
Distance to the building = 510 meters
Therefore, the total distance traveled by the sound = 510 meters * 2 = 1020 meters
Time taken for the echo to return = 3 seconds
The speed of sound is calculated by dividing the total distance traveled by the time taken.
Speed of sound = Total distance traveled / Time taken
Speed of sound = 1020 meters / 3 seconds
Speed of sound = 340 meters per second
The correct option for the approximate speed of sound in the air is B. 340 meters per second.