Reference:
https://docs.microsoft.com/en-us/azure/vpn-gateway/vpn-gateway-howto-site-to-site-resource-manager-portal

Scenario: Create a workflow to send an email message when the settings of VM4 are modified.
You can start an automated logic app workflow when specific events happen in Azure resources or third-party resources. These resources can publish those events to an Azure event grid. In turn, the event grid pushes those events to subscribers that have queues, webhooks, or event hubs as endpoints. As a subscriber, your logic app can wait for those events from the event grid before running automated workflows to perform tasks - without you writing any code.
References:
https://docs.microsoft.com/en-us/azure/event-grid/monitor-virtual-machine-changes-event-grid-logic-app
Topic 2, Humongous Insurance
Overview
Existing Environment
Huongous Insurance is an insurance company that has three offices in Miami, Tokoyo, and Bankok. Each has 5000 users.
Active Directory Environment
Humongous Insurance has a single-domain Active Directory forest named humongousinsurance.com. The functional level of the forest is Windows Server 2012.
You recently provisioned an Azure Active Directory (Azure AD) tenant.
Network Infrastructure
Each office has a local data center that contains all the servers for that office. Each office has a dedicated connection to the Internet.
Each office has several link load balancers that provide access to the servers.
Active Directory Issue
Several users in humongousinsurance.com have UPNs that contain special characters.
You suspect that some of the characters are unsupported in Azure AD.
Licensing Issue
You attempt to assign a license in Azure to several users and receive the following error message: "Licenses not assigned. License agreement failed for one user." You verify that the Azure subscription has the available licenses.
Requirements
Planned Changes
Humongous Insurance plans to open a new office in Paris. The Paris office will contain 1,000 users who will be hired during the next 12 months. All the resources used by the Paris office users will be hosted in Azure.
Planned Azure AD Infrastructure
The on-premises Active Directory domain will be synchronized to Azure AD.
All client computers in the Paris office will be joined to an Azure AD domain.
Planned Azure Networking Infrastructure
You plan to create the following networking resources in a resource group named All_Resources:
Default Azure system routes that will be the only routes used to route traffic A virtual network named Paris-VNet that will contain two subnets named Subnet1 and Subnet2 A virtual network named ClientResources-VNet that will contain one subnet named ClientSubnet A virtual network named AllOffices-VNet that will contain two subnets named Subnet3 and Subnet4 You plan to enable peering between Paris-VNet and AllOffices-VNet. You will enable the Use remote gateways setting for the Paris-VNet peerings.
You plan to create a private DNS zone named humongousinsurance.local and set the registration network to the ClientResources-VNet virtual network.
Planned Azure Computer Infrastructure
Each subnet will contain several virtual machines that will run either Windows Server 2012 R2, Windows Server 2016, or Red Hat Linux.
Department Requirements
Humongous Insurance identifies the following requirements for the company's departments:
Web administrators will deploy Azure web apps for the marketing department. Each web app will be added to a separate resource group. The initial configuration of the web apps will be identical. The web administrators have permission to deploy web apps to resource groups.
During the testing phase, auditors in the finance department must be able to review all Azure costs from the past week.
Authentication Requirements
Users in the Miami office must use Azure Active Directory Seamless Single Sign-on (Azure AD Seamless SSO) when accessing resources in Azure.

Reference:
https://docs.microsoft.com/en-gb/azure/cost-management-billing/costs/tutorial-acm-create-budgets
https://docs.microsoft.com/en-us/azure/cost-management-billing/costs/cost-mgt-alerts-monitor-usage-spending

Reference:
https://blog.kloud.com.au/2018/10/19/address-space-maintenance-with-vnet-peering/
https://docs.microsoft.com/en-us/azure/virtual-network/virtual-network-manage-peering#requirements-andconstraints

Explanation
You should use a policy definition.
Reference:
https://docs.microsoft.com/en-us/azure/azure-policy/policy-definition