For each of the following studies, identify the type of graph (histogram, time series graph, or scatter diagram) that would be the most appropriate. (You can use more than one graph of each type, for example, two histograms.)

a. Are stock returns more volatile than bond returns?

b. Do interest rates affect home construction?’

c. Is the rate of inflation higher or lower now than in the past?

d. Do cigarette sales depend on cigarette prices?

e. Is there more variation in the unemployment rate or the rate of inflation?