In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.
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Question: Question: Ian is digging in his garden, and admires the shiny pebbles sitting in the yard, as he digs a hole and finds more rocks, he knows that the first ones he found are 
 Answer: younger

Answer: Older rocks are at the bottom and younger rocks are at the top.


Question: Question: Mona is excavating a deep tunnel as part of an exploratory committee. As she bores deeper in to the Earth, what can she expect will happen to the temperature? 
 Answer: increase

Answer: Temperature increases with depth inside the Earth, so melting of rocks is more likely to occur at greater depths.


Question: Question: If Milo decreases the concentration of hydrogen ions in his swimming pool, what happens to the acidity of his pool? 
 Answer: decreases

Answer:
With a higher concentration of hydrogen ions, a solution is more acidic but has a lower pH.