To change the Cloud Billing account for a project, you need to be able to move a project from one Cloud Billing account to another. To accomplish this task, you need permissions adequate to unlink the project from the existing Cloud Billing account AND to link the project to the target Cloud Billing account. Roles with adequate permissions to perform this task: Project Owner or Project Billing Manager on the project, AND Billing Account Administrator or Billing Account User for the target Cloud Billing account

Reference link- https://cloud.google.com/billing/docs/how-to/modify-

An identity platform is a modern solution for managing the identities of users and devices in a centralized fashion.
Reference: https://www.okta.com/blog/2021/07/what-is-an-identity-platform/#:~:text=An%20identity%
20platform%20is%20a,%2C%20integrations%2C%20and%20platform%20services
Text Description automatically generated

Because this will enable the business to better serve their users.

Explanation
The above is a real world example of a company named Planet, where they sent around 80+ satellites to take pictures of earth every day, 24 hours. They run around 40,000 preemptible VMs concurrently.
Preemptible instances function like normal instances but have the following limitations:
Compute Engine might stop preemptible instances at any time due to system events. The probability that Compute Engine will stop a preemptible instance for a system event is generally low, but might vary from day to day and from zone to zone depending on current conditions.
Compute Engine always stops preemptible instances after they run for 24 hours. Certain actions reset this
24-hour counter.
Preemptible instances are finite Compute Engine resources, so they might not always be available.
Preemptible instances can't live migrate to a regular VM instance, or be set to automatically restart when there is a maintenance event.
Due to the above limitations, preemptible instances are not covered by any Service Level Agreement (and, for clarity, are excluded from the Compute Engine SLA).
The Google Cloud Free Tier credits for Compute Engine do not apply to preemptible instances.
Text Description automatically generated

Reference link- https://cloud.google.com/compute/docs/instances/preemptible