Cavity and solid walls. 1  A cavity wall is made up of two walls with a gap in between, known as the cavity; the outer leaf is usually made of brick, and the inner layer of brick or concrete block.  A solid wall has no cavity; each wall is a single solid wall, usually made of brick or stone.
A cladogram (from Greek clados branch and gramma character) is a diagram used in cladistics which shows relations among organisms.
Rhombus vs Parallelogram. A parallelogram is a quadrilateral or four-sided figure in which the opposite sides are parallel. And because the opposite lines are parallel, hence the opposite angles are also equal. A rhombus, on the other hand, may be defined as an equilateral parallelogram.