Winnie's Window Cleaning is a small local operation. Winnie presently cleans the outside windows in her neighbours' houses for $36 per house. She does ten houses a day. She is incurring total costs of $420 and of this amount $100 is fixed. The average variable cost per house is constant.
a. At a price of $36, what is her break-even level of output?
b. If she cannot increase her output in the short run, should she shut down?