(a)[2]
Determine the real distance between boat $A$ and boat $B$, in kilometres.
(b)[2]
Using only compasses and a straight edge, construct the locus of points that are equally distant from $A$ and $B$.
(c)[1]
A ship, $S$, is at the same distance from $A$ as from $B$. $S$ lies on a bearing of $105^\circ$ from $A$. Indicate and name the position of $S$ on the scale drawing.