Many species of fungus exist in the environment, but only some cause infections. The primary source of most infections is soil. Fungal infections can be acquired by inhalation, ingestion, or through the skin (for example, through a cut or wound).
Squares are quadrilaterals in which all four sides and all four angles have equal measurements. Rectangles have four angles with equal measurements, and the opposite sides also have equal measurements. All squares are rectangles, but not all rectangles are squares. Trapezoids have exactly one pair of parallel sides. Rhombuses have four sides with equal measurements, and opposite pairs of sides are parallel. All rhombuses are parallelograms, but not all parallelograms are rhombuses. All squares are rhombuses, but not all rhombuses are squares.
Some parallelograms, such as rectangles and squares, contain right angles. Another type of parallelogram, known as a rhombus, may or may not contain right angles. Quadrilaterals are closed, co-planar geometric shapes that comprise two diagonals and four sides, where all four interior angles have a sum of 360 degrees. Special types of quadrilaterals include parallelograms, rectangles, squares, rhombuses, trapezoids and kites. Parallelograms contain two pairs of opposing sides that are parallel and equally long. The opposite angles of parallelograms are also equal. Rectangles, squares and rhombuses are considered parallelograms because they share the same properties as a parallelogram. The four interior angles of rectangles and squares are all right angles, or 90-degree angles. The opposite angles, also called supplementary angles, have a sum of 180 degrees.