23) Ampro-Mag is a small company that makes materials for safely controlling hazardous spills of all kinds. It sells these items as a neutralizing kit priced at $120. The costs of the materials that go into each kit are $45. It costs $5 in labour to assemble a kit. The company has monthly expenses of $1,000 for rent and insurance, $200 for heat and electricity, $500 for advertising in trade journals, and $3,500 for the monthly salary of its owner. What is Ampro-Mag's monthly break-even point in terms of number of neutralizing kits sold? (Please show your calculation steps)