A company has budgeted $$100,000$ in manufacturing overhead costs for $10,000$ machine hours. At the end of the month, only $7,500$ men incurred. What is the overhead cost spending and volume variance in dollars?

a$.$ $$20,000($favorable$)$

b$.$ $$25,000($favorable$)$

c$.$ $$20,000($unfavorable$)$

d$.$ $$25,000($unfavorable$)$