How to find premises - 2 examples

[Kasia@EconomistGMAT]

1. In the past few weeks, John, who is a teacher, has been arriving home late. When asked by Jane about this behavior, he muttered something about having lots of pressure at work. Jane has also noticed that he talks on his cellular phone in a hushed voice, but hangs up when she enters the room. Jane concluded that John must be leading a double life as a secret agent.

2. The Takuur Swamp frog is well-known mainly due to the peculiar protrusion that appears on the top of its head. Archaeological findings show that the Takuur and its evolutionary ancestor are almost identical, except for the ancestor's slightly larger protrusion. Originally believed to be decorative, research being performed by a team of zoologists is leading them to believe that the protrusion belonging to the Takuur's ancestor was used by the frog to swat insects on which it fed.

Try to select premises in the two arguments above.

Argument 1:
The first three sentences are premises providing factual data. The last sentence uses the conclusion word concluded so it's Jane's conclusion:

Premise A: John has been arriving home late recently
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Premise B: John claimed that the reason for his late arrivals is an increased work load
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Premise C: John whispers privately on his phone and hangs up immediately when Jane enters the room
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Jane's Conclusion: John is a secret agent

Possible assumption: John secretive behavior can only mean one thing - conspiracy!


Argument 2:
The first two sentences are premises which provide factual data; the last sentence contains the zoologists' belief based on their research, i.e., their conclusion:

Premise A: the Takuur frog has a "thing" on its head
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Premise B: the Takuur frog and its evolutionary ancestor are very similar, although the ancestor's head "thing" was a bit larger
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Premise C: the head "thing" was once believed to be decorative
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Zoologists' hypothesis: the Takuur's ancestor used the "thing" to kill flies which it then ate.