The mass of an electron is a higher than the mass of the proton or the neutron b equal to the mass of the proton and a neutron or c not significant to the overall mass of the atom

The mass of an electron is C. not significant to the overall mass of the atom

Atoms are composed of 3 types of basic particles namely protons, electrons, and neutrons

The charge of 1 proton is equal to a charge of 1 electron but has a different sign

The proton is positively charged (+1), the electron is negatively charged (-1). and neutrons not charged (neutral)

For a charge of 1 electron = e = 1.66.10⁻¹⁹ coulomb

Whereas the neutron charge = 0

The mass of this basic particle is expressed in atomic mass units  

This atomic unit uses the standard atomic mass, that is, the C-12 isotope

1 atom C-12 = 12 atomic mass units

1 atomic mass unit = 1/12 x 1 C-12 atomic mass

The hydrogen atom is the lightest atom whose mass is 1.67 x 10⁻²⁷kg (measured using a mass spectrometer) and simplified to 1 amu (atomic mass unit).

1 amu = 1,66.10⁻²⁴ grams

The mass of each basic particle in atomic mass units is:

The proton mass is considered to be equal to 1 atomic mass unit and a neutron which is also considered to be equal to 1 atomic mass unit

So if we look at the numbers above, it shows that the electron mass is smaller than the proton mass and neutron mass, and not significant to the overall mass of the atom

The subatomic particle that has the least mass  

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element 2512X  

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about subatomic particles statement  

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answer and explanation;

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form