Exercise 1: One Subnet vs. Multiple Subnets for the Same Real Resilience — Possible Solution
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AWS Fundamentals' own capstone needed separate public and private
subnets, and needed those subnets duplicated across multiple
Availability Zones, because in AWS's own real model a subnet is
permanently bound to exactly one specific AZ. Achieving real
multi-zone resilience there genuinely requires one subnet per zone,
since placing a resource in a particular zone means choosing the
matching zone-specific subnet.

Azure's own real model, covered in Chapter 5, works fundamentally
differently: a Virtual Network, and every subnet inside it, spans ALL
Availability Zones in the region at once. Subnet choice and
Availability Zone placement are two entirely independent decisions in
Azure -- a single subnet can host resources across every zone in the
region, with each individual resource's own zone assigned
independently at creation time, not determined by which subnet it
happens to sit in.

ANSWER: Step 3 needed only one subnet because Azure subnets
inherently span every Availability Zone in the region already -- the
real multi-zone resilience AWS achieves through multiple zone-bound
subnets, Azure achieves within a single subnet, by assigning each
resource's own zone independently at creation. This is exactly
Chapter 5's own biggest structural difference from AWS, applied
concretely in this capstone.

WHY THIS WORKS AS AN ANSWER
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This correctly identifies the specific real structural cause (subnet-
to-zone binding in AWS vs. subnet-spans-all-zones in Azure) rather
than vaguely saying "Azure networking is simpler," and explicitly
connects the capstone's own design choice back to Chapter 5's own
central, named structural difference.