Explanation:
Box 1: Yes
A public cloud is a web-based service model in which a hosting provider offers shared resources, like apps, servers and storage, to the general public. It's a multi- tenant environment, with different customers using the same pool of IT infrastructure. You pay for these shared resources on a pay-as-you-go basis.
Box 2: Yes
Box 3: Yes
Microsoft Azure is an example of a public cloud. In a public cloud, you share the same hardware, storage and network devices with other organizations or cloud tenants and you access services and manage your account using a web browser.
Reference:
https://www.rackspace.com/library/what-is-a-public-cloud
https://www.techtarget.com/searchcloudcomputing/definition/Windows-Azure