Im not to good at geography but I think you are correct :)
Speed of wave = Frequency x Wavelength
so Speed = 0.7 x 9 = 6.3
remember the calculations must be done in their Basic SI units.
therefore, you have to convert 7 mm to meters which becomes 0.7 meters
Answer:
A
Explanation:
the horizontal and vertical force acting on it consist a net force on the inclined direction (30degrees below the horizontal) you can tell by the length of the horizontal component (try to see the 30degree incline as horizontal, because that's the direction of the displacement). net work done on the system results in an increase in energy. i hope this can help :D, i'm also taking the ap physics 1 exam tommorow.
Interference if the hardest to remove due to the superposition of the frequencies of the radio waves
D. Light as light is a wave