Jamaal is allowed to walk no farther than three blocks in either direction from his house. If his house is located on the 57th block of the town, which absolute value equation can be used to determine the farthest block to which Jamaal is allowed to walk? |x – 57| = 0
|57 – 3| = x
|3 – 57| = x
|x – 57| = 3

Knowledge of the physicochemical properties of potential chemical alternatives is a requirement of the alternatives assessment process for two reasons. First, the inherent hazard of a chemical, such as its capacity to interfere with normal biological processes, and its physical hazards and environmental fate (degradation, persistence) are determined by its intrinsic physicochemical properties and the system with which it is interacting. For organic and inorganic chemicals, these intrinsic properties are determined by molecular structure, while for materials, they are determined by composition, size, structure, and morphology. Second, physicochemical properties can be used to eliminate from consideration chemicals that are likely to exhibit particular physical or toxicological hazards. As important as these data are, obtaining them is relatively fast and inexpensive, and can be readily done at the initial stages of the alternatives assessment.