(a)[1]
Measure the angle of incidence $i$ for the ray at point $M$.
(b(i))[1]
At $M$, the angle of refraction is $22^{\circ}$. On Fig. 3.1, draw the refracted ray inside the glass block.
(b(ii))[1]
Use the letter $N$ to label the point at which the refracted ray leaves the glass block.
(c(i))[1]
The ray leaves the glass block at $N$ without any further deviation. Draw the ray path after it has left the glass block.
(c(ii))[1]
Describe how the student uses optics pins to mark the path of the ray accurately.