The Williams Company Can Convert to ACH Disbursing for $20,000

The Williams Company can convert to ACH disbursing for $20,000.Williams averages a perpetual 500 checks per month and has an annual cost of capital of 10%.If ACH disbursing will save Williams 20 cents per payment,what is the NPV of the decision to convert to ACH?

A) -$10,000
B) -$8,000
C) -$3,000
D) $2,000
E) $4,000