The outer shining surface of a round bottom steel bowl acts as a __________ mirror.

Explanation

To determine what type of mirror the outer shining surface of a round bottom steel bowl acts as, we can follow these steps:

### Step-by-Step Solution

1. **Identify the Surface of the Bowl**: The question specifies the "outer shining surface" of a round bottom steel bowl. This implies that we are looking at the exterior surface of the bowl.

2. **Understand the Shape of the Bowl**: A round bottom steel bowl has a curved surface that bulges outward. This is an important characteristic because the shape of the surface determines how it reflects light.

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