## Work description

Create 3D CAD models of the building vent products offered in construction projects. Provide also exploded views of the vent products to show how to assemble them.

The provided reference images are for visual style guidance only. The models must be built to the dimensional specifications listed below.

### Vent types

1. Mushroom Head Ventilation:
- Commonly used in RVs, motorhomes, and trailers.
- Installed on roofs to allow fresh air in and release excess moisture and indoor air, preventing mold growth and damp conditions.
- Dimensions:
   - Bottom plate diameter: 18", with 7 bolt holes - Bolt 5/16'' x 3 3/8''
   - Middle plate diameter: 17", with 3 bolt holes - Bolt 3/16'' x 1 1/8''
   - Mushroom head cover diameter: 18", height: 9".

2. Whirlybird Ventilation:
- Recognizable by its dome shape, it is a wind-powered system used in warmer climates.
- Reduces high temperatures in summer and removes excess humidity in winter.
- The dome has engineered fins that rotate in the wind, creating a vacuum to extract hot air.
- Dimension:
   - Bottom plate diameter: 18", with 7 bolt holes - Bolt 5/16'' x 3 3/8''
   - Middle plate diameter: 17.5", with 3 bolt holes - Bolt 3/16'' x 1 1/8''
   - Dome diameter: 16", height: 9.5".

## Provided material

- A photo of the mushroom head vent type in `inputs/Mushroom Head Ventilation Reference.png`
- A photo of the whirlybird vent type in `inputs/Whirlybird Ventilation Reference.png`

## Design & Assembly Assumptions

The specifications above provide the primary control dimensions. You are expected to apply standard design practices for all undefined geometry, including:

- Component Geometry: Design logical, functional shapes (e.g., raised necks, flanges) to create a stackable assembly from the listed parts. The 'Bottom plate' and 'Middle plate' must be designed with interlocking features (e.g., hexagonal, star-shaped, etc.) to ensure proper alignment. The specific geometry of this interlock is not defined and is left to the designer's discretion.
- Bolt Placement: Use standard Bolt Circle Diameters (BCDs) appropriate for the given plate diameters.
- Mushroom Head Vent Internals: No need to model the internals. Just model the mounting and housing for the vent.
- Whirlybird Internals: Model a simplified, standard internal assembly (axle, bracing, etc.) to ensure the exploded view is mechanically complete.

## Deliverables

- 3D CAD Models in .stp/.step format of the Mushroom Head Vent and Whirlybird Vent
- 3D CAD Models in .stp/.step format of the exploded Mushroom Head Vent and Whirlybird Vent
- Exploded view assembly drawings (PDF format) showing bolt sizes and indicating component names.