(Use the Following Information to Answer the Next Six Questions

(Use the following information to answer the next six questions.)
A manufacturer is interested in selecting one of three companies to deliver (by truck) its product to its distributors and wholesalers in a certain area. Each of the companies has different operating procedures and uses different routes. Assuming that certain minimum standards for delivery time are achieved, the manufacturer wants to select the company with the lowest unit shipping cost.
In addition, the manufacturer believes that the type of packaging used for the product may have an impact on shipping cost and is considering two types of packaging. It is unknown whether or not any of the three companies under consideration is better equipped to handle either type of packaging.
After using each of the companies for five deliveries of the product with each of the types of packaging (thus, each company made a total of 10 deliveries, with all deliveries under similar circumstances) , the shipping costs per unit were calculated and are shown below:

-The sum of squares for the interaction term in the above problem can be calculated as

A)
B) SS_PC - SS_P - SS_C.
C) SS_T - SS_TR.
D) SS_TR - SS_P - SS_C.
E) none of the above.