Explanation:

Box 1: RepositoryUpdated
When a new version of the ContentAnalysisService is available the previous seven days of content must be processed with the new version to verify that the new version does not significantly deviate from the old version.
Box 2: service
Box 3: imageCollection
Reference:
https://docs.microsoft.com/en-us/azure/devops/notifications/oob-supported-event-types

Scenario: You must perform a point-in-time restoration of the retail store location data due to an unexpected and accidental deletion of data.
Before you enable and configure point-in-time restore, enable its prerequisites for the storage account: soft delete, change feed, and blob versioning.
Reference:
https://docs.microsoft.com/en-us/azure/storage/blobs/point-in-time-restore-manage

Explanation

Box 1: internal
caching-type
Choose between the following values of the attribute:
* internal to use the built-in API Management cache,
* external to use the external cache as Azure Cache for Redis
* prefer-external to use external cache if configured or internal cache otherwise.
Box 2: private
downstream-caching-type
This attribute must be set to one of the following values.
* none - downstream caching is not allowed.
* private - downstream private caching is allowed.
* public - private and shared downstream caching is allowed.
Box 3: Authorization
<vary-by-header>Authorization</vary-by-header>
<!-- should be present when allow-private-response-caching is "true"--> Note: Start caching responses per value of specified header, such as Accept, Accept-Charset, Accept-Encoding, Accept-Language, Authorization, Expect, From, Host, If-Match Reference:
https://docs.microsoft.com/en-us/azure/api-management/api-management-caching-policies

The New-AzResourceGroup cmdlet creates an Azure resource group.
The New-AzAppServicePlan cmdlet creates an Azure App Service plan in a given location The New-AzWebApp cmdlet creates an Azure Web App in a given a resource group The New-AzWebAppSlot cmdlet creates an Azure Web App slot.
References:
https://docs.microsoft.com/en-us/powershell/module/az.resources/new-azresourcegroup?view=azps-2.3.2
https://docs.microsoft.com/en-us/powershell/module/az.websites/new-azappserviceplan?view=azps-2.3.2
https://docs.microsoft.com/en-us/powershell/module/az.websites/new-azwebapp?view=azps-2.3.2
https://docs.microsoft.com/en-us/powershell/module/az.websites/new-azwebappslot?view=azps-2.3.2

Explanation

Box 1: SAS tokens
Custom topics use either Shared Access Signature (SAS) or key authentication. Microsoft recommends SAS, but key authentication provides simple programming, and is compatible with many existing webhook publishers.
In this case we need the expiration time provided by SAS tokens.
Box 2: ValidationCode handshake
Event Grid supports two ways of validating the subscription: ValidationCode handshake (programmatic) and ValidationURL handshake (manual).
If you control the source code for your endpoint, this method is recommended.