How many atoms are in 15.6 grams of silicon?

a. a primary source combines several different accounts of an event. b. a primary source generally benefits from having been written after an event.

explanation:

warm front forms when a moist, warm air mass slides up and over a cold air mass. as the warm air mass rises, it condenses into a broad area of clouds. a warm front brings gentle rain or light snow, followed by warmer, milder weather.

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