How do I graph the curve of the marginal cost?

1) Arthur decided to start his own web design company. The company can generate $150,000 per yearin revenue. Arthur's costs are $20,000 per year in equipment and software licenses plus other $10,000per year in rent for the office. If Arthur was not working at his own company, he would be working at hisprevious company YTZ designs making $120,000 per year in salary and benefits.C) If each week he works at his company costs Arthur $2500 in lost wages, what is the shape ofthe marginal cost curve? Is it increasing, decreasing or constant?