Answer
Please see the work below.
Work Step by Step
(a) We can find the number of electrons as follows:
$N_p=\frac{M}{m_p}$
$\implies N_p=\frac{4.56\times 10^{-23}}{1.673\times 10^{-27}}=2.73\times 10^4 protons$
$q_e=Q-q_p$
$\implies q_e=1.84\times 10^{-15}-(2.73\times 10^4)(1.6\times 10^{-19})=-2.53\times 10^{-15}C$
Now $N_e=\frac{q_e}{-e}$
We plug in the known values to obtain:
$N_e=\frac{-2.53\times 10^{-15}}{-1.6\times 10^{-19}}$
$N_e=1.58\times 10^4electrons$
(b) We can find the number of protons as
$N_p=\frac{M}{m_p}$
$\implies N_p=\frac{4.56\times 10^{-23}}{1.673\times 10^{-27}}=2.73\times 10^4 protons$