Question: A manufacturer of PC monitors is interested in the effects that the type of glass and the type of phosphor used in the manufacturing process have on the brightness of the monitors. The director of research and development has received anecdotal evidence that the type of glass does not affect the brightness of the monitor as long as phosphor type 2 is used. However, the evidence seems to indicate that the type of glass does make a difference if two other phosphor types are used. Here are data to validate this anecdotal evidence.

Conduct a procedure to verify or repudiate the anecdotal evidence.