please calculate ACTIVITY VARIANCE for materials and supplies in November. Show work!

Gotthelf Clinic uses client-visits as its measure of activity. During December, the clinic budgeted for 2,500 client-visits, but its actual level of activity was 2,480 client-visits. The clinic has provided the following data concerning the formulas used in its budgeting and its actual results for December: Personalexpenses:xed33,500rable18.702,5,004italpersonal:80,25033,500187022,480=37480,875 The spending variance for medical supplies in December would be closest to: A. $1,030F B. $856U C. $856F D. $1,030U