State whether the following statements are true or false:
Birds do not cast shadows when they fly at a great height.

Explanation

To determine whether the statement "Birds do not cast shadows when they fly at a great height" is true or false, we can analyze the situation step by step.

### Step-by-Step Solution:

1. **Understanding Shadows**: Shadows are created when an object blocks light from a light source, such as the sun. The size and visibility of a shadow depend on the distance between the object (in this case, the bird), the light source, and the surface (the ground) where the shadow is cast.

2. **Effect of Height on Shadows**: When an object, like a bird, flies at a great height, the distance between the bird and the ground (where the shadow would be cast) increases significantly.

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