Blood urea nitrogen (BUN) is a measure of the amount of urea in the blood (R). It provides useful information about your health. The liver produces urea as a waste product of the digestion of proteins (R, R). Urea is a safe vehicle to get rid of excess nitrogen from the body.
Algebra is important for future employment opportunities in Californiaâs increasingly knowledge-based economy, even in jobs con-sidered to be âblue collar.â For example, an applicant must have passed Algebra I to enter an electrician apprenticeship program. But if students are aiming for college, algebra is essential.
Two key features of algebra as we understand the word today are: 1. Reasoning about numbers by recognizing patterns across numbers; 2. Solving a problem by introducing a term for an unknown and then, starting with what is known, reasoning to determine its value. We first see the emergence of both features of algebra in the mathematics of ancient Babylonia, around 2,000 BCE. Several hundred of the many thousands of Babylonianâs cuneiform-inscribed clay tablets that have been found are devoted to mathematics.