Three students are considering operating a fruit smoothie stand during their summer break. This is an alternative to summer employment with a local firm, where they would each earn $6,000 over the three-month summer period. A fully equipped facility can be leased at a cost of $8,000 for the summer. Additional projected costs are $1,000 for insurance and $2.20 per unit for materials and supplies. Their fruit smoothies would be priced at $5 per unit. What is the economic breakeven number of units for this operation? (Assume a $5 price and ignore interest costs associated with the timing of lease payments.)