Final answer:
The diary by Lucky Noah from 1870's Idaho is a primary source as it's a first-hand account of his personal experiences. Therefore, you should mark it as 'P'.
Step-by-step explanation:
The diary titled 'Life in the Mines' from a miner named Lucky Noah who lived in Idaho in the 1870’s is considered a primary source. Primary sources provide firsthand accounts or direct evidence concerning a topic under investigation. They are usually created by witnesses or recorders who experienced the events or conditions being documented. Primary sources are usually distinguished from secondary sources, which cite, comment on, or build upon primary sources. In this case, Lucky Noah's diary would be a direct account of his personal experiences working in the mines. Therefore, it is a primary source, so it should be marked with a 'P'.
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