Kidney stones, also known as urolithiasis, are a common affliction of the urinary tract.
No. In order for a quadrilateral to be a trapezoid, it must have exactly one pair of parallel sides. A right trapezoid, therefore, has exactly one pair of right angles. However a square would be a right parallelogram (which is the current definition of a rectangle). In the UK, the word trapezoid refers to a quadrilateral with no sides parallel. They use the word trapezium to refer to what Canadians call a trapezoid. To make matters worse, North Americans call a quadrilateral with no parallel sides a trapezium. Here's a summary.
b = base. h = height.Depends what shape. A rectangle or square is length x width. A trapezoid is h/2(b1 +b2). A triangle is 1/2bh. A circle is pi x r^2.