
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Suppose that each of the 5 persons knows a piece of information, each piece is different, about a certain event. Each time person  $A$  calls person  $B$ ,  $A$  gives  $B$  all the information that  $A$  knows at that moment about the event, while  $B$  does not say to  $A$  anything that he knew.

(a) What is the minimum number of calls are necessary so that everyone knows about the event?
(b) How many calls are necessary if there were  $n$  persons?

Present the answer in LaTex format: \boxed{Your answer}
user