Testing a new pain-relief tablet. Paracetamol is the active ingredient in drugs designed to relieve mild to moderate pain and fever. The properties of paracetamol tablets derived from khaya gum were studied in the Tropical Journal of Pharmaceutical Research (June 2003). Three factors believed to affect the properties of parcetamol tablets are (1)

the nature of the binding agent, (2) the concentration of the binding agent, and (3) the relative density of the tablet.

In the experiment, binding agent was set at two levels

(khaya gum and PVP), binding concentration at two levels (.5% and 4.0%), and relative density at two levels (low and high). One of the dependent variables investigated in the study was tablet dissolution time (i.e., the amount of time, in minutes, for 50% of the tablet to dissolve). The goal of the study was to determine the effect of binding agent, binding concentration, and relative density on mean dissolution time.

a. Identify the dependent (response) variable in the study.

b. What are the factors investigated in the study? Give the levels of each.

c. How many treatments are possible in the study? List them.