The frequency of the middle a note on a piano is 440 what is the wavelength of this note in centimeters? the speed of sound in air is 343.06

explanation:

you do 343.06 ➖ 440 and then you take your answer and see what times what equals that number

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

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since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.