From a point in the interior of an equilateral triangle, perpendiculars are drawn on the three sides. If the lengths of the perpendiculars are a, b and c, find the altitude of the triangle.

A teacher measures the heights of 9 students in her class as follows (in centimetres) 145 , 116 , 111 , 121 , 118 , 126 , 147 , 152 , 119 What is the median of their heights?