Which atom is it?

Electricity and Magnetism Level 4

The electric charge density inside an atomic nucleus of radius \(R\) is \[\rho (r) = {\rho}_{0} \left[1-{\left(\frac{r}{R}\right)}^{2}\right].\] If \({\rho}_{0} = 5 \times {10}^{25}\text{ C/m}^{3}\) and \(R = 3.4 \times {10}^{-15}\text{ m}\), what is the total charge?

Express your answer to the nearest elementary charge (should be an integer).

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