While the letter grade to numerical contribution for a single subject is ordinal, the moment you compute a grade point average you already treated it as interval at that moment (otherwise you have no basis on which to assert that A+C = B+B).
No. 4 squared is 16 and 16 + 79 is 85 not 88
The altitude of a shape or a polygon can be determined by drawing a perpendicular line from the base to the top most part of the polygon. In this case, the altitude is the segment BC where the ends are on the topmost of the cylinder and the base of the cylinder.
