The accompanying summary data on CeO2 particle sizes (nm) under certain experimental conditions as read from a

Question:

The accompanying summary data on CeO2 particle sizes (nm) under certain experimental conditions as read from a graph in the article "Nanoceria-Energetics of Surfaces, Interfaces and Water Adsorption" (J. of the Amer. Ceramic Soc., 2011: 3992-3999):

a. What proportion of the observations are less than 5?
b. What proportion of the observations are at least 6?
c. Construct a histogram with relative frequency on the vertical axis and comment on interesting features. In particular, does the distribution of particle sizes appear to be reasonably symmetric or somewhat skewed?
d. Construct a histogram with density on the vertical axis and compare to the histogram in (c).

Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...