To determine which set of side lengths will form a triangle, we can use the Triangle Inequality Theorem. This theorem states that for any three sides \( a \), \( b \), and \( c \) of a triangle, the following conditions must hold:
- \( a + b > c \)
- \( a + c > b \)
- \( b + c > a \)
Let's evaluate each option:
Option 1: Side lengths 3, 3, 6
- Check the inequalities:
- \( 3 + 3 > 6 \) → \( 6 > 6 \) (not true)
- \( 3 + 6 > 3 \) → \( 9 > 3 \) (true)
- \( 3 + 6 > 3 \) → \( 9 > 3 \) (true)
Since the first condition fails, this set of lengths does not form a triangle.
Option 2: Side lengths 6, 8, 10
- Check the inequalities:
- \( 6 + 8 > 10 \) → \( 14 > 10 \) (true)
- \( 6 + 10 > 8 \) → \( 16 > 8 \) (true)
- \( 8 + 10 > 6 \) → \( 18 > 6 \) (true)
All conditions are satisfied, so this set of lengths forms a triangle.
Option 3: Side lengths 4, 6, 13
- Check the inequalities:
- \( 4 + 6 > 13 \) → \( 10 > 13 \) (not true)
- \( 4 + 13 > 6 \) → \( 17 > 6 \) (true)
- \( 6 + 13 > 4 \) → \( 19 > 4 \) (true)
Since the first condition fails, this set of lengths does not form a triangle.
Based on the evaluations:
- Option 1: Does not form a triangle.
- Option 2: Forms a triangle.
- Option 3: Does not form a triangle.
Thus, the response indicating which set of lengths the carpenter can use for the triangular design is:
\[
\boxed{\text{Option 2}}
\]