Answer
a) 1.5 cm
b) 1.1 cm
Work Step by Step
(a) We know that
$ h_i=-\frac{d_i}{d_{\circ}}\times h_{\circ}$
We plug in the known values to obtain:
$ h_i=-\frac{2.5cm}{320cm}$
$ h_i=-1.48cm $
The negative sign indicates that the image on the retina is inverted.
(b) As $ h_i=-\frac{d_i}{d_{\circ}}\times h_{\circ}$
We plug in the known values to obtain:
$ h_i=-\frac{2.5cm}{420cm}$
$ h_i=1.1cm $
