A chemical process involves adding various agents to a vat and then waiting for the agents to react to make a final compound. The vat holds up to 1000 gallons. Chemical agents are added to the vat at a rate of 4.5 gallons per minute. Once the agents have been added to the vat, the reaction takes 85 minutes no matter the actual number of gallons in the batch. After the batch is complete, the vat must be cleaned. Cleaning always takes 15 minutes. What is the setup time of this process? 

a. 15 minutes 

b. 85 minutes 

c. 100 minutes 

d. 222.22 minutes