The data set provided contains U.S. regular retail gasoline prices (cents/gallon) from August 20, 1990 to January 2, 2012, from a national sample of gasoline stations obtained from the U.S. Department of Energy.
a) Create a histogram of the data and describe the distribution.
b) Create a time series plot of the data and describe the trend.
c) Which graphical display seems the more appropriate for these data? Explain.