(a)[3]
Olav travels from $A$ to $B$ at a steady speed of $4\text{ m/s}$ and then from $B$ to $C$ at a steady speed of $3\text{ m/s}$. He then travels from $C$ to $A$ at a constant speed. His average speed over the complete trip is $3.6\text{ m/s}$. Calculate his speed when he travels from $C$ to $A$.
(b)[4]
Use the cosine rule to determine angle $BAC$.
(c(i))[1]
Determine the bearing of $B$ from $A$.
(c(ii))[2]
Determine the bearing of $A$ from $B$.
(d)[2]
$D$ is the point on $AC$ closest to $B$. Calculate the distance from $D$ to $A$.