The average wavelength in a series of ocean waves is 15.0 meters. A wave crest arrives at the shore on an average of every 10.0 seconds, so the frequency is 0.100 Hz. What is the average speed of the waves?

d. air pressure decreases as altitude increases.

which three statements are true about all alloys?

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me