A solid conducting sphere of radius $2\mathrm{.}00$ cm has a charge $8\mathrm{.}00$C$.$ A conducting spherical shell of inner radius $4\mathrm{.}00$ cm and outer radius $5\mathrm{.}00$ cm is concentric with the solid sphere and has a total charge of $-3\mathrm{.}00$C$.($Take radially outward as the positive direction.$)$

$($a$)$ Find the electric field at r $=1\mathrm{.}00$ cm from the center of this charge configuration.

MN$/$C

$($b$)$ Find the electric field at r $=3\mathrm{.}00$ cm from the center of this charge configuration.

MN$/$C

$($c$)$ Find the electric field at r $=4\mathrm{.}50$ cm from the center of this charge configuration.

MN$/$C

$($d$)$ Find the electric field at r $=7\mathrm{.}00$ cm from the center of this charge configuration.

MN$/$C