Replica A counted 2 adds and replica B counted 3 adds. Type the merged counter value.

Answer: ______________

Replicas receive the same updates in different orders. What makes them converge?

• A merge that erases order: commutative, associative, idempotent
• A faster network between replicas
• A leader that reorders all updates

With a concurrent add and remove of one element, the merge rule decides the outcome.

Circle one:   True   False

A set uses add-wins. An add and a remove of one photo race. What does every replica show?

• The photo is absent everywhere
• Each replica keeps its own answer
• The photo is present everywhere

The same add arrives at a replica twice. What is the effect of the duplicate?

• It corrupts the replica state
• It counts twice
• Nothing, it folds into the same state

Why can these replicas accept writes with no coordination?

• Writes are never stored durably
• Conflicts are settled later by the merge
• Networks never reorder their messages

A block list must never show a blocked account, even if an unblock raced a block. Which rule fits?

• Add-wins, to keep entries longer
• Remove-wins, so the block survives races
• Last-writer-wins by wall clock

Kim says her merged set always matches what the users intended. What is wrong?

• Merges are always too slow to matter
• The rule picks mechanically and may surprise everyone
• Replicas can never actually converge