7.
in the diagram, the line segments ha and abc
represent the course of a ship which left a harbour
h at noon to sail to a and then c at a uniform
speed. ha = 12 km and hb = 20 km. zhab = 90°
and b is due west of h.
(a)
find the distance ab.
(b) find the bearing of a from h.
(c) the ship reached b at 2 p. m.
(i) find the uniform speed of the ship.
(ii) if the ship reached c at 3 p. m., find the
distance and the bearing of c from h.