The CFO wants to implement a chargeback model where each department is billed exactly for the cloud resources they consume. Currently, all departments deploy resources into a single shared GCP project. How should you architect the billing solution?

Create a separate Billing Account for each department.

Use IAM roles to restrict how much money each department can spend.

Require all resources to be tagged with a 'department' label, export billing data to BigQuery, and create a Looker Studio dashboard.

Use the GCP Pricing Calculator at the end of each month to estimate costs.