Maria Eagle is a Native American artisan. She works part time making bowls and mugs by hand from special pottery clay and then sells her items to the Beaver Creek Pottery Company, a Native American crafts guild. She has 60 hours available each month to make bowls and mugs, and it takes her 12 hours to make a bowl and 15 hours to make a mug. She uses 9 pounds of special clay to make a bowl, and she needs 5 pounds to make a mug; Maria has 30 pounds of clay available each month. She makes a profit of $300 for each bowl she delivers, and she makes $250 for each mug. Determine all the possible combinations of bowls and mugs Maria can make each month, given her limited resources, and select the most profitable combination of bowls and mugs Maria should make each month. Develop an Excel spreadsheet and a graph to help solve this problem.