Problem $2\mathrm{.}3$:

Table $2\mathrm{.}5$ contains a summary of local speed data for $172$ vehicles observed during normal days. Analyze the data.

a$)$ Plot a cumulative frequency curve and a histogram;

b$)$ Calculate the minimum and median speeds and display these values on the cumulative frequency curve; and

c$)$ Explain your opinion about the data distribution and the reliability of the calculated minimum speed to represent the minimum speed of all vehicles using the related road.

Table $2\mathrm{.}5$: Local speeds data.

$\backslash$table$[[$Speed Class $($km$/$h$),$Frequency$],[20-25,1],[25-30-,9],[30-35,18],[35-40,34],[40-45,31],[45-50,27],[50-55,25],[55-60,13],[60-65,6],[65-70,4],[70-75,3],[75-80,1]]$