(a(i))[1]
State the mathematical name for this sort of angle.
(a(ii))[1]
Determine the value of $x$.
(a(iii))[1]
Determine the value of $y$.
(b)[1]
Show that the mean angle in any triangle is $60^{\circ}$.
(c)[3]
Calculate the value of $h$.
(d(i))[2]
Calculate $PR$.
(d(ii))[2]
Calculate $BC$.
(e)[4]
Calculate the perimeter of this triangle.