Fields contracts to have a marble structure made in his likeness. Fields contracts with Marble Builders, Inc create the sculpture for $150,00. Marble Builders anticipates making a net profit of $75,000 for the sculpture. It spends $25,000 to buy the marble and begins work sculpting the piece. After sculpting began Fields breaches the contract and tells Marble Builders he doesn't want the sculpture anymore. Unfortunately, Marble Builders is unable to use the piece of marble anymore but is able to find another person to create a sculpture for during the time it would have taken to complete Fields sculpture. This sculpture is anticipated to net Marble Builders a profit of $20,000. If Marble Builders sues Fields, how much if any can it recover from fields?

I am confused on the conditions for calculating damages for breach of contracts