Rename dividing decimals to dividing decimals 4
Retitle file
Dividing an integer by simple decimal
Include decimals representing mutliples of a quarter
Dividing decimals 3 exercise
Start dividing decimals 2
lint on solid_geometry, created volume_1
improve hints: fix #58118
Merge remote-tracking branch 'upstream/master' into div-dec
Dividing decimals 2 - some times the answer is a decimal
More changes...
Added a "sketch" to graphie-3d  for 3d line drawings.
Added units to the answers, changed out \Box for "?", added a 3D figure to box-minus-box, and made a few numbers latex which were not.
suggestion from spicyj

not sure if the numbers should be in code tags, but i think it looks better that way.
Added an problem with a fixed box to count the cubes of (to practice 3d imagination).  Also added a "weird shape" problem which generates a random shape with between 3 and 7 cubes.
Updated graphie-3d to use the painters algorithm.  Added a few more problem types to volume 1.
added some more options to graphie-3d, weird shape now looks snazzier.
Broke volume_1 into 3 more reasonable exercises.  Volume_with_unit_cubes is just basic understanding of volume by counting cubes.  Volume_1 builds an understanding of the formula for the volume of right rectangular prisms.  Volume_2 uses the knowledge built in Volume_1 for more advanced or creative problems.  Everything is still at the 5th grade level.
ensure that EXPR1 is not divisible by EXPR2, fix #58979
Fixed style issues.