Introduction

Here are broad strokes for the two short answer questions. Grade according to the core idea with consideration for presentation (formatting/grammar/spelling/punctuation). The weigh is 6:4 (60% on idea; 40% on presentation).

Question 1

Q. CI's suggestion for a "single source repository" seems to suggest or even require a centralized source control tool/system. How does a project using a decentralized source control system such as git implement this core CI practice? (100 words)

A. A decentralized source control system nonetheless affords one particular copy of a repo to be designated as canonical ("the official copy"). NB: git by itself is sufficient to act as a server. See https://git-scm.com/book/en/v2/Git-on-the-Server-Setting-Up-the-Server. However for simplicity, it is more common today to use a service (such as GitHub) to host the repo and to add additional niceties.

Question 4

Q. How does git enable the developers of a geographically and intermittently-connected team to "commit to the mainline every day"? (Assume that "intermittently-connected" means some team members are disconnected from the network for 1-2 days at a stretch.) (100 words)

A: The workflow of every developer--even those who are sporadically connected--does not change. Every developer follows the same practice of making changes, testing and committing irrespective of their backend's network connection. When a developer is connected, he/she can share (push) their changes with their team.