State and calculate the projection of AF on the plane EFGH, given the dimensions of cuboid ABCDEFGH.

Here's a step-by-step solution:

Given dimensions of the cuboid ABCDEFGH:

• Length $AB = 12 \text{ cm}$
• Width $BC = 8 \text{ cm}$
• Height $AH = 4 \text{ cm}$ (This means $AE = BF = CG = DH = 4 \text{ cm}$)

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Part (a): State and calculate the projection of AF on the plane EFGH.

1. State the projection:
   • The plane EFGH is the top face of the cuboid.
   • To find the projection of line AF onto plane EFGH, we project each endpoint of the line segment onto the plane.