Bonnie Company applies overhead based on machine hours. The variable overhead standard is $15$ hours at $$10$ per hour. During March, Bonnie spent $$144,100$ for variable overhead, and $13,100$ machine hours were used to produce $800$ units. What is the variable overhead efficiency variance?

Question $9$ options:

$$24,100$ unfavorable

$$11,000$ favorable

$$11,000$ unfavorable

$$13,100$ unfavorable