Fill in the blanks.
(i) The line segment joining a vertex of a triangle to the midpoint of its opposite side is called a __P__ of the triangle.
(ii) The perpendicular line segment from a vertex of a triangle to its opposite side is called an __Q__ of the triangle.
(iii) A triangle has __R__ altitudes and __S__ medians.
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A
A
A
A
Please label the options correctly