Explanation
The app must be running in the Standard, Premium, or Isolated tier in order for you to enable multiple deployment slots. If the app isn't already in the Standard, Premium, or Isolated tier, you receive a message that indicates the supported tiers for enabling staged publishing. At this point, you have the option to select Upgrade and go to the Scale tab of your app before continuing.
Scale up: Get more CPU, memory, disk space, and extra features like dedicated virtual machines (VMs), custom domains and certificates, staging slots, autoscaling, and more.
Scale out: Increase the number of VM instances that run your app. You can scale out to as many as 30 instances Reference:
https://docs.microsoft.com/en-us/azure/app-service/deploy-staging-slots
https://docs.microsoft.com/en-us/azure/app-service/manage-scale-up

Explanation:

Instead you should delete VM1. You recreate VM1, and then you add the network interface for VM1.
Note: When you create an Azure virtual machine (VM), you must create a virtual network (VNet) or use an existing VNet. You can change the subnet a VM is connected to after it's created, but you cannot change the VNet.
References:
https://docs.microsoft.com/en-us/azure/virtual-machines/windows/network-overview

Explanation

As cooling period and scale in and scale out durations are not displayed in the graphical view, so we need to consider the default values as below for these settings.
Cool down (minutes) : The amount of time to wait before the rule is applied again so that the autoscale actions have time to take effect. Default is 5 minutes.
Duration : The amount of time monitored before the metric and threshold values are compared. Default is 10 minutes.
Box 1: 4 virtual machines
The Autoscale scale out rule increases the number of VMs by 2 if the CPU threshold is 80% or higher for more than or equals to 10 mins due to default duration for scale in and out is 10 minutes. Since CPU utilization at 85% only lasts for 6 mins , it does not trigger the rules.
Hence no of virtual machines will be same as the initial value which is 4.
Box 2: 4 virtual machines
The Autoscale scale in rule decreases the number of VMs by 4 if the CPU threshold is 30% or lower for more than or equal to 10 mins. due to default duration for scale in and out is 10 minutes . Since CPU utilization at
30% only lasts for 6 mins , it does not trigger the rules. Hence after first 6 mins instance count will be same as initial count as 4. After that CPU utilization reached to 50% for 6 mins , which again would not trigger the scale in rule. Therefore no of virtual machines will be same as the initial value which is 4.
References:
https://docs.microsoft.com/en-us/azure/azure-monitor/platform/autoscale-overview
https://docs.microsoft.com/en-us/azure/azure-monitor/platform/autoscale-best-practices
https://docs.microsoft.com/en-us/azure/azure-monitor/platform/autoscale-common-scale-patterns

https://docs.microsoft.com/en-us/azure/virtual-machines/extensions/dsc-overview
https://docs.microsoft.com/en-us/azure/virtual-machine-scale-sets/tutorial-install-apps-template
https://docs.microsoft.com/en-us/samples/mspnp/samples/azure-well-architected-framework-sample-state- configuration
https://docs.microsoft.com/en-us/azure/architecture/framework/devops/automation-configuration