If a snowstorm is predicted in Chicago, then the conditions should be
upper air temperature = low
surface temperature = high
air pressure = low
For a snowstorm to occur, warm air must rise above cold air. The pressure must also be below atmospheric pressure.<span />
Rhinoviruses are transmitted through the air or via contact. We might expect this sort of transmission to require a fairly healthy host (one who gets out and comes into contact with others) and, hence, to select against virulent strains. If we take precautions and try to stay away from people or avoid any contact with people, more hand-washing stations, increased attention to sanitization, and isolation of patients will help to reduce the transmission of the disease and, in the process, may favor the evolution of less virulent strains of the virus.
Quantitative analytic methods refer to methods used in analytical chemistry in order to determine the concentration or the moles of a certain substance in solutions. This includes finiding correct units. The most appropriate answer is a quantitative variable and this is the first choice; Quantitative analytic methods can help you determine or estimate the amount of poison in the blood (solvent).