Final answer:
The speed of sound under standard atmospheric conditions is about 768 miles per hour, which rounds to approximately 800 mph, making the correct answer (3) 800 mph.
Step-by-step explanation:
Under standard atmospheric conditions, the speed of sound is typically around 343 meters per second (m/s) at sea level at a temperature of 21°C. To convert this speed into miles per hour (mph), we can use the conversion factor where 1 meter per second is approximately equal to 2.24 miles per hour. Multiplying 343 m/s by 2.24 gives us the speed of sound in miles per hour:
343 m/s × 2.24 mph/(m/s) = 768.32 mph
Therefore, under standard conditions, the speed of sound is about 768 mph, which makes the closest choice from the provided options:
- 600 mph
- 700 mph
- 800 mph
- 900 mph
The correct answer is (3) 800 mph, which is the approximation to the nearest hundred.