Current Attempt in Progress

Spherical refracting surfaces. When an object is placed $15$ cm in front of a spherical refracting surface the image distance is $-14$ cm $.$ The index of refraction of the refracting material is $2\mathrm{.}8$ and it is embedded in transparent material with index of refraction $1\mathrm{.}7.$ Find $($a$)$ the radius of curvature $\backslash ($ r $\backslash )$ of the surface $($including the sign$)$ and determine whether the image is $($b$)$ real or virtual and $($c$)$ on the same side of the surface as object $\backslash ($ O $\backslash )$ or on the opposite side.

$($a$)$ Number

Units

$($b$)$

$($c$)$