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04-spatial-operations.Rmd

@@ -33,8 +33,8 @@ Spatial operations on raster objects include subsetting --- covered in Section \
 *Map algebra* covers a range of operations that modify raster cell values, with or without reference to surrounding cell values.
 The concept of map algebra, vital for many applications, is introduced in Section \@ref(map-algebra); local, focal and zonal map algebra operations are covered in sections \@ref(local-operations), \@ref(focal-operations), and \@ref(zonal-operations), respectively. 
 Global map algebra operations, which generate summary statistics representing an entire raster dataset, and distance calculations on rasters, are discussed in Section \@ref(global-operations-and-distances).
-Next, relation between map algebra and vector operations are discussed in Section \@ref(map-algebra-counterparts-in-vector-processing).
-In the final section before the exercises (\@ref(merging-rasters)) the process of merging two raster datasets is discussed and demonstrated with reference to a reproducible example.
+Next, the relationships between map algebra and vector operations are discussed in Section \@ref(map-algebra-counterparts-in-vector-processing).
+In the  Section \@ref(merging-rasters),1 the process of merging two raster datasets is discussed and demonstrated with reference to a reproducible example.
 
 ```{block2 04-spatial-operations-2, type='rmdnote'}
 It is important to note that spatial operations that use two spatial objects rely on both objects having the same coordinate reference system, a topic that was introduced in Section \@ref(crs-intro) and which will be covered in more depth in Chapter \@ref(reproj-geo-data).