Which of the following is a scientific question that can be answered through experimentation?
a.
when looking at a map, you ask, "how are the borders of germany determined? "
c.
when sitting with friends in class, you ask, "how many protons does an atom of iron have? "
b.
when talking to your teacher, you ask, "what is the definition of matter? "
d.
when looking at a building, you ask, "will the materials used in this building withstand acid rain? "

The frequency of a tuning fork can be found by the method shown. a long tube open at both ends is submerged in a beaker of water, and the vibrating tuning fork is placed near the top of the tube. the length l of the air column is adjusted by moving the tube vertically. the sound waves generated by the fork are reinforced when the length of the air column corresponds to one of the resonant frequencies of the tube. the smallest value for l for which a peak occurs in sound intensity is 7 cm. l what is the frequency of the tuning fork? the speed of sound in air is 345 m/s. answer in units of hz