A chef needs to choose a pan that will allow food to cook as quickly as possible for a special recipe and has decided that he will use one of three pans. Each pan has the same dimensions and design but is made of a different type of metal. The chef will design an experiment that will test and rank the thermal conductivity of the pans by cooking a hamburger patty to an internal temperature of 170 ºF in each pan on the same stove burner. The thermal conductivity is the rate of transfer of energy in the form of heat over a period of time through a material. Describe how thermal conductivity can be measured and compared for each of the pans. Identify the dependent and independent variables and one controlled variable in the experiment. Enter your answer in the space provided.