My question is not about below question per say. I need help in understanding when to use Exhibit 13B1 and 13B2. For example, I was told that I need to use Exhibit 13B-2 for the below problem, but I am not sure why or the difference. I have other problems that I need to do so I am hoping to better understand the difference between the 2. Thanks.

1. The management of Opray Corporation is considering the purchase of a machine that would cost $360,000, would last for 7 years, and would have no salvage value. The machine would reduce labor and other costs by $78,000 per year. The company requires a minimum pretax return of 11% on all investment projects. (Ignore income taxes.)

See separate Exhibit 13B-1 and Exhibit 13B-2, to determine the appropriate discount factor(s) using the tables provided.

The net present value of the proposed project is closest to:

A) $15,646

B) $89,588

C) $7,536

D) $186,000