Able Industries Has the Following Information Is Related to Its $\bullet$

Able Industries has the following information is related to its adjusting entries at the end of December.
$\bullet$ Services have been performed for customers that have not yet been billed or paid totaling $100.
$\bullet$ The office equipment computation for 2010 depreciation amounts to $480.
What is the net effect that the necessary adjusting entries for this information have on net income for Able?
a. $380 increase.
b. $380 decrease.
c. $580 increase.
d. $580 decrease.