Reveiw the vector related eps

Thoughts on improving the vector related eps

In the tip "how should I define my bounding box", use an online viewer, for example this one, to determine the bounding box.
The point/line/polygon image seems to be redundant in this ep
The two-step bounding box cropping seems to be redundant. We can put the cx function cropping as an exercise: let the participants read in all the data, read the clip/cx/clip_by_rectdocumentation, and do the same cropping by themselves.
The existing line data seem to be redundant. And fixing the rotated line data was also not super interesting. Maybe this part can be replaced by some more practical techniques, e.g. using sjoin to query the soil type (a larger polygon) for crop parcel.

Visualizing the thumbnail with polygons seems to be redundant. One can directly jump to copping large raster with the bounding box and visualize polygons on the cropped raster.
Explain the rio.clip function and demonstrate clipping with all polygons. Add an exercise to let students choose a subset of the polygons (e.g. choose a certain type of crop), and crop the same raster using the subsetted polygons
The variable names are too long, and need to be improved. Use the term "crop" only for data cropping, but not for field plants.
remove the waterway exercise

Do the Zonal statistics per polygon, but not per type of crop
Visualize the rasterized results
Exercise: discuss why some polygon ids are missing in the rasterized data. (solution: some polygons are in the same pixel)
Demonstrate zonal stats on non-missing polygons.
exercise: design a way to make sure all polygons can get their statistics (solution: iterative way)