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modules/image_pixels.md

@@ -25,17 +25,17 @@ layout:    page
 * Check where the lowest pixel indices are in the displayed image:
         * Most commonly: Upper left corner, which is different to conventional coordinate systems.
 
-### Activity: Explore image calibration
+## Activity: Explore image calibration
 
-* Open image: xyz_8bit_calibrated_anisotropic__mri_head.tif 
+* Open image: xyz_8bit_calibrated_anisotropic__mri_head.tif
 * Check the calibration of this image
 * Explore how image calibration affects spatial measurements, e.g.,
   * Measure the distance between two pixels in the image
   * Measure the size of an image region
-* Appreciate that image calibration might be neccessary, e.g. 
+* Appreciate that image calibration might be neccessary, e.g.
   * 3D distance measurements
 * Appreciate that image calibration can be confusing, e.g.
-  * not consistently used in image filter parameter specification 
+  * not consistently used in image filter parameter specification
 
 ## Formative assessment
 
@@ -44,12 +44,6 @@ True or false?
 * The lowest pixel index of a 2D image always is `[1,1]`.
 * When looking at a 2D image, the lowest pixel indices are always in the lower left corner.
 
-### Formative assessment
-
-Answer below questions:
-
-* Given a voxel spacing of (100 nm, 100 nm, 300 nm), what is the distance between the voxels at indices [10, 5, 11] and [2, 20, 13]? 
-
 ## Learn next
 
 - display.md