Assuming an ideal gas, the speed of sound depends on temperature
only. Air is almost an ideal gas.
Assuming the temperature of 25°C in a "standard atmosphere", the
density of air is 1.1644 kg/m3, and the speed of sound is 346.13 m/s.
The velocity can't be specified, since the question gives no information
regarding the direction of the sound.
Rock layers are folded and appear to be scratched because of the plate tectonics and the glacial advance.
Answer: Option 1 and 2.
<u>Explanation:</u>
Plate tectonics and the glacial advance are the geological phenomenon which have the power to effect the layers of the rock. Because of these, there can be scratches on the layers of the rock and the layers of the rocks can be folded.
The huge mass of ice that is included in the glacier which may be of thickness of three to four kilometers is a lot to scratch the rocks. These glaciers are responsible for moving the rocks from their original position to a new place altogether.