The rails expand during the heat of a summer day
Answer:
so the third one
Explanation:
During the day, the sun heats up mountain air rapidly while the valley remains relatively cooler. Convection causes it to rise, causing a valley breeze. At night, the process is reversed. During the night the slopes get cooled and the dense air descends into the valley as the mountain wind.
Answer: 205000000 microliter
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