What is AWS’s billing policy regarding stack resources?

You are playing around with setting up stacks using JSON templates in CloudFormation to try and understand them a little better. You have set up about 5 or 6 but now start to wonder if you are being charged for these stacks.

What is AWS’s billing policy regarding stack resources?
A .  You are not charged for the stack resources if they are not taking any traffic.
B .  You are charged for the stack resources for the time they were operating (even if you deleted the stack right away)
C .  You are charged for the stack resources for the time they were operating (but not if you deleted the stack within 60 minutes)
D .  You are charged for the stack resources for the time they were operating (but not if you deleted the stack within 30 minutes)

View Answer

Answer: B

Explanation:

A stack is a collection of AWS resources that you can manage as a single unit. In other words, you can create, update, or delete a collection of resources by creating, updating, or deleting stacks. All the resources in a stack are defined by the stack’s AWS CloudFormation template. A stack, for instance, can include all the resources required to run a web application, such as a web server, a database, and networking rules. If you no longer require that web application, you can simply delete the stack, and all of its related resources are deleted.

You are charged for the stack resources for the time they were operating (even if you deleted the stack right away).

Reference: http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/stacks.html