John is traveling north at 20 meters/second and his friend Betty is traveling south at 20 meters/second. If north is the positive direction, what are John and Betty's speeds? Which statement best illustrates vibrational motion?

No because scientist are still changing there mines today so they are not correct to this day

B.air resistancehoped i   can i get brainliest

The waves slow downn

Jenny and fred both play a long note on their trombones. a stationary observer hears the sound increasing and decreasing repeatedly in loudness. which of these must be true? the sound waves from the two trombones have slightly different frequencies.the sound waves from the two trombones have the same frequency.the sound waves from the two trombones have slightly different amplitudes.the sound waves from the two trombones have the same wavelength.the sound waves from the two trombones have slightly different velocities.  lolthe answer is          the sound waves from the two trombones have slightly different frequencies.