In Snowflake, the ownership privilege for a schema includes:
Automatic granting to the creator's role: The role that creates a database object within the schema automatically receives ownership of that object.
Ability to manage grants: Ownership enables the role to manage permissions and grants on the schema and its objects, allowing them to control access at the schema level.
Ownership does not directly confer query privileges or the ability to alter warehouse settings, nor is it transferable without specific privilege management actions.

A Pre-signed URL should be used to access files stored in a Snowflake stage without requiring authentication into Snowflake. Pre-signed URLs are simple HTTPS URLs that provide temporary access to a file via a web browser, using a pre-signed access token. The expiration time for the access token is configurable, and this type of URL allows users or applications to directly access or download the files without needing to authenticate into Snowflake5.

Snowflake's unique architecture is described as a multi-cluster, shared data architecture that leverages massively parallel processing (MPP). This architecture separates compute and storage resources, enabling Snowflake to scale them independently. It does not use a single cluster or rely solely on symmetric multiprocessing (SMP); rather, it uses a combination of shared-nothing architecture for compute clusters (virtual warehouses) and a centralized storage layer for data, optimizing for both performance and scalability.
Reference:
Snowflake Documentation: Snowflake Architecture Overview

User-level network policies in Snowflake can be created by roles with the necessary privileges to manage security and account settings. The ACCOUNTADMIN role has the highest level of privileges across the account, including the ability to manage network policies. The SECURITYADMIN role is specifically responsible for managing security objects within Snowflake, which includes the creation and management of network policies.
Reference:
[COF-C02] SnowPro Core Certification Exam Study Guide
Snowflake Documentation on Network Policies1
Section 1.3 - SnowPro Core Certification Study Guide