Rewrite the following sentences in reported speech

I. Rewrite the following sentences in reported speech.
1. "I think there are 9 planets in the solar system," David said.
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2. "Do you think aliens from other planet may contact us one day in the future?" Tom
asked.
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3. "How can scientists discover the surface of other planet?" Dean asked Tom.
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4. "When can people travel to the Mars as tourists?" Edward asked his friends.
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5. "Will aliens be friendly to people on Earth?" Nick asked his father.
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6. "How many stars are there in our galaxy?" Tom asked.
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7. "How long does it take a space buggy to travel to Mercury?" Dean asked.
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8. "How old is our Earth?" Linda asked.
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9. "I believe one day in the future aliens might visit the Earth," Robert said.
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10. "How can we send message to other planets?" Carlos asked.
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