RStudio project initialization
Downloaded data file
Read and clean data
Produce a reasonable-looking histogram
I like newlines
Do not attempt to convert strings to factors
Combine date and time, which will be more convenient for plotting
Second plot, time-series
Save plot to PNG as specified.
Plot 2 result
Important comment!
Save plot to PNG as specified.
Plot 1 result
For consistency and good sense, take filename parameter