A researcher wants to investigate how weight depends on height among adult males in Europe. She visits five regions in Europe and determines the average heights in those regions to be 1.80, 1.78, 1.77, 1.77, and 1.80 meters. The corresponding average weights are 87.1, 86.9, 83.0, 84.1, and 86.4 kg, respectively. 

(a) What is the domain and the range of the relation? 

(b) Express the relation using a mapping. 

(c) Express the relation as a set of ordered pairs.