Step 1: Calculate the volume of each box.
The volume of each box is given by:
\[
\text{Volume of each box} = 8 \times 10 \times 12 = 960 \, \text{cubic inches}.
\]
Step 2: Calculate the number of boxes needed.
To store 288,000 cubic inches, the number of boxes needed is:
\[
\text{Number of boxes} = \frac{288,000}{960} = 300 \, \text{boxes}.
\]
Step 3: Calculate the total value of the order.
Each box contains one hat, and each hat is valued at \$7.50. The total value of the order is:
\[
\text{Total value} = 300 \times 7.50 = 1,350.
\]
Conclusion:
Thus, the minimum value of the order is \$1,350, and the correct answer is (B) \$1,350.