Define the constraints.

**Question 12 options:**

(a) Operations time definition:
\[ T_{ass} = 2x_1 + 4x_2 + 3x_3 + 7x_4 \quad \text{(assembly)} \]
\[ T_{pol} = 3x_1 + 2x_2 + 3x_3 + 4x_4 \quad \text{(polish)} \]
\[ T_{pac} = 2x_1 + 3x_2 + 2x_3 + 5x_4 \quad \text{(pack)} \]

(b) Operations time limits:
The operation time limits depend upon the situation being considered. In the first situation, where the maximum time that can be spent on each operation is specified, we simply have:
\[ T_{ass} \leq 100000 \quad \text{(assembly)} \]
\[ T_{pol} \leq 50000 \quad \text{(polish)} \]
\[ T_{pac} \leq 60000 \quad \text{(pack)} \]

- Both (a) and (b)
- None of the above