1. We all laughed and cried. 2. It was very exciting! 3. But after a time, Mr Carter said we must all be quiet.

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Q: What does #1 mean? Does #1 mean that we all laughed while we cried? Did we laugh and cry at the same time?

Q: What does 'it' refer to in #2?

1 seems to be describing their extreme joy and relief in what they found.

In 2, 'it' seems to refer to the discovery.