The best statement would be number 3. Sound waves move perpendicular to the medium particles.
Answer:
6.817 x 10^-4
Explanation:
You first need to put the decimal between the ones and tenths (6.8), then you count back to the original decimal point. If you are counting to the left then its going to be a negative exponent but if you count towards the right, it'll be a positive exponent. So from 6.817 to 0.0006817, it is 4 places back. Thats how you get the answer. Hope this helps a bit
Answer: One of the units used to measure incident energy is calories per centimeter squared (cal/cm2).
Explanation: Incident energy this is defined as the amount of thermal energy impressed on a surface, at a certain distance from the source, generated during an electrical arc event.
The working distance is the distance from where the worker stands to the source location. The most common distance for which incident energy has been determined in tests is 18 inches.
Answer:
The answer to your question is: v = 121.46 m/s
Explanation:
Data
h = 30 m
vo = ?
dx = 300 m
Formula
t = 
speed = distance / time
Process
t= 2.47 s
speed = 300 / 2.47
speed = v = 121.46 m/s
