Question

A solid is drilled using a cylindrical drill in the given direction. How many surfaces will the solid have after the drilling is complete? 

Hint:

Drilling with a cylinder adds 3 new surfaces: 2 circles + 1 curved surface. Always add to the original cube’s 6.

Answer 1

Step 1: Original solid.
The initial cube has 6 surfaces.
Step 2: Drilling effect.
Drilling introduces:
- 2 new circular surfaces at entry and exit points.
- 1 continuous curved cylindrical surface inside.
Step 3: Total.
\[ 6 + 3 = 9 \] Final Answer: \[ \boxed{9 \, \text{surfaces}} \]