Question: Upon request guests can enjoy breakfast in their room
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Answer: Upon request guests can enjoy breakfast in their room.

Question: This is a separate also more easy to handle failure
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Answer: This is a separate, also more easy to handle failure.

Question: The four sites were selected because they have different types of metal contamination
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Answer: The four sites were selected because they have different types of metal contamination.

Question: Karin is a nurse by profession and Tommy runs an advertisement agency and when time allows it practices art that covers the walls of the building
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Answer:
Karin is a nurse by profession and Tommy runs an advertisement agency and, when time allows it, practices art that covers the walls of the building.