How to put cross-sectional into a research design?

The correct answer is  ait's a process by which rocks and minerals undergo in their composition^o^

Hi.the measurement  amperes represents the rate at which current flows.it's like the measurement of water flowing through a pipe.~

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.

The answer would ve running