Following is a list of questions I conceived or found on the Internet and then answered.

Who is the main point of contact for billing or account questions if a user has an AWS account with an Enterprise-level AWS Support plan?

AWS Concierge Support Team

What is one technique to provide unified billing if each department within a firm has its own AWS account?

Create an AWS Organization from the payer account and invite the other accounts to join.
Reference: https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/consolidated-billing.html

The use of what AWS feature or service allows companies to track and categorize spending on a detailed level?

Cost allocation tags.
Reference: https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/cost-alloc-tags.html

Which service AWS environments to find opportunities that can save money for users and also improve system performance?

AWS Trusted Advisor

Which Amazon EC2 pricing model allow customers to use existing server-bound software licenses?

Dedicated Hosts
Reference: https://aws.amazon.com/ec2/pricing/

Which AWS characteristics make AWS cost effective for a workload with dynamic user demand?

Elasticity and Pay-as-you-go pricing

What costs are included when comparing AWS Total Cost of Ownership (TCO) with on-premises TCO?

Data center security

Which AWS tools assist with estimating costs?

Cost allocation tags
AWS Simple Monthly Calculator
AWS Total Cost of Ownership (TCO) Calculator

List advantages of AWS consolidated billing?

The ability to receive one bill for multiple accounts
Potential volume discounts, as usage in all accounts is combined
Reference: https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/consolidated-billing.html

Which of the following Reserved Instance (RI) pricing models provides the highest average savings compared to On-Demand pricing?

Three-year, All Upfront, Standard RI pricing
Reference: https://aws.amazon.com/ec2/pricing/reserved-instances/pricing/

Compared with costs in traditional and virtualized data centers, AWS has:

lower variable costs and lower upfront costs

Which AWS feature will reduce the customer’s total cost of ownership (TCO)?

Elastic computing

A customer is using multiple AWS accounts with separate billing. How can the customer take advantage of volume discounts with minimal impact to the AWS resources?

Use the consolidated billing feature from AWS Organizations.
Reference: https://aws.amazon.com/answers/account-management/aws-multi-account-billing-strategy/

Which Amazon EC2 instance pricing model can provide discounts of up to 90%?

Spot Instances
Reference: https://aws.amazon.com/ec2/spot/

Which Reserved Instance (RI) pricing model can change the attributes of the RI as long as the exchange results in the creation of RIs of equal or greater value?

Convertible RIs
Reference: https://aws.amazon.com/ec2/pricing/reserved-instances/

Which service should a customer use to consolidate and centrally manage multiple AWS accounts?

AWS Organizations
Reference: https://aws.amazon.com/organizations/

Which tasks may be used to improve Amazon EC2 costs?

Implementing Auto Scaling groups to add and remove instances based on demand.
Purchasing Reserved Instances.

Which of the following price options would result in the highest reduction after making an Amazon EC2 Dedicated Host reservation?

All upfront payment
Reference: https://aws.amazon.com/ec2/pricing/reserved-instances/pricing/

List capabilities of the AWS Cost Management tools?

Break down AWS costs by day, service, and linked AWS account.
Create budgets and receive notifications if current of forecasted usage exceeds the budgets.

List cost components should be addressed when developing a cloud Total Cost of Ownership (TCO) model for AWS workloads?

Compute costs
Storage costs
Data transfer costs
Reference: https://aws.amazon.com/blogs/aws/the-new-aws-tco-calculator/

Which AWS Cost Management tool allows you to view the most granular data about your AWS bill?

AWS Cost and Usage Report
The Cost & Usage Report is your one-stop-shop for accessing the most granular data about your AWS costs and usage. You can also load your cost and usage information into Amazon Athena, Amazon Redshift, AWS QuickSight, or a tool of your choice.
Reference: https://aws.amazon.com/aws-cost-management/

Which pricing construct provides the MOST cost-effective solution to migrate an application that is running non-interruptible workloads for a three-year time frame.

Amazon EC2 Reserved Instances

Which Reserved Instance (RI) pricing models can change the attributes of the RI as long as the exchange results in the creation of RIs of equal or greater value?

Convertible Reserved Instances

When performing a cost analysis that supports physical isolation of a customer workload, which compute hosting model should be accounted for in the Total Cost of Ownership (TCO)?

Dedicated Hosts.

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