Accounting procedures allow a business to evaluate their inventory costs based on two methods: LIFO (Last In First Out) or FIFO (First In First Out). A manufacturer evaluated its finished goods inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the difference, they computed (FIFO - LIFO) for each product. Based on the following results, does the LIFO method result in a lower cost of inventory than the FIFO method?

Product FIFO (F) LIFO (L)

1 225 221

2 119 100

3 100 113

4 212 200

5 248 245

What is the null hypothesis?

Select one:

a. H0: d= 0

b. H0: d 0

c. H0: d 0

d. H0: d 0