Answer:
(a) has the highest frequency
Explanation:
E = hf...where E(is the energy of a photon);h(is the planck's constant) and f is the frequency of the photon
Whereby this formula shows us that energy of a photon is directly proportional to its frequency
So hence if the energy is high then the frequency of the photon is also high
You need to know the time as well.
Y-STR analysis. It is a DNA test used to compute and match with the possibility via lap.
A beat is an interference pattern between two sounds of slightly different frequencies, perceived as a periodic variation in volume whose rate is the difference of the two frequencies. Frequency beat is equal to,

The reference frequency in our case would be 392Hz, and since there is the possibility of the upper and lower range for the amount of beats per second that the two possible frequencies are heard would be


Therefore the two possible frequencies the piano wire is vibrating at, would be 396Hz and 388Hz