Geometry

Question Analysis：
Applies intersecting mirror principles to optical device design.

Key Concept Explanation：
Periscope Mechanics: Output angle = 2 × mirror angle
Standard Design: 45° mirrors → 90° turn
Modified Case: 30° mirrors → 60° turn

Step-by-Step Solution：
Original setup: 45° → 90° (verifies 2θ rule)
New angle: θ = 30°
Calculate: 2 × 30° = 60°
Direction depends on mirror arrangement

Option Analysis：
A) Incorrect: Default case value
B) Incorrect: Default case value
C) Correct: Proper calculation
D) Incorrect: Supplementary angle error

Common Mistakes：
Assuming angle preservation
Using relative mirror positions incorrectly
Confusing in...