Explanation:
Box 1 : 4
As there are 4 distinct set of resource types (Ingress, Egress, Delete storage account, Restore blob ranges), so you need 4 alert rules. In one alert rule you can't specify different type of resources to monitor. So you need 4 alert rules.
Box 2 : 3
There are 3 distinct set of "Users to notify" as (User 1 and User 3), (User1 only), and (User1, User2, and User3). You can't set the action group based on existing group (Group1 and Group2) as there is no specific group for User1 only. So you need to create 3 action group.

Reference:
https://docs.microsoft.com/en-us/azure/azure-monitor/platform/action-groups

Explanation:

"A resource can only be created in a virtual network that exists in the same region and subscription as the resource." https://learn.microsoft.com/en-us/azure/virtual-network/virtual-network-vnet-plan-design- arm#regions

Before creating a network interface, you must have an existing virtual network in the same location and subscription you create a network interface in.
If you try to create a NIC on a location that does not have any Vnets you will get the following error: "The currently selected subscription and location lack any existing virtual networks. Create a virtual network first." Reference:
https://docs.microsoft.com/en-us/azure/virtual-network/virtual-network-network-interface