Final answer:
The customer's total bill for a 3-hour service call at a rate of $45 for the call plus $25 per hour of work comes to $120. Therefore, the correct answer to the question, "What will the customer's bill be if the plumber conducts a service call that takes 3 hours?" is d. $120.
Step-by-step explanation:
The total bill for a customer whose service call takes 3 hours from a plumber charging $45 for a service call plus $25 for each hour of work would be calculated as follows:
- Service call charge: $45
- Charge per hour ($25) for 3 hours: 3 * $25 = $75
- Total charge: Service call charge ($45) + Hourly charge ($75) = $120
Therefore, the correct answer to the question, "What will the customer's bill be if the plumber conducts a service call that takes 3 hours?" is d. $120.