I would say, C. Because an controlled variable is an experimental element which is constant and unchanged throughout the course of the investigation.
These organelles are the-- cell walls,vacuoles,cytoplasm,chloroplasts,nucleus, and cell membrane.
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Answer:
Explanation:
Are waves produced as a result of a vibration between an electric field and magnet field
<span>Carbon is the 15th most abundant element in the Earth's crust, and the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen</span>