Beatrice Math Tutors offers two tutoring models: individual and group. The individual model provides one$-$on$-$one tutoring while the group model consists of group of no more than four students. The individual model has a budgeted average price of $$326.$ The group model has a budgeted average price of $$92.$ The manager of the tutoring center believes that $65$ percent of the customers will choose the group model. The individual model averages $$202$ and the group model averages $$62$ in budgeted variable cost. The manager estimates that about $160$ people will purchase tutoring services in any month.

For October, the tutoring center served a total of $170$ customers, including $110$ that chose the group option.

Required:

a$.$ Compute the sales activity variance for the tutoring center for October.

b$.$ Compute the mix and quantity variances for October.