What does the number tell us about an atom that never changes

All cells are made of four types of acids, lipids, proteins, and carbohydrates.

An unknown insoluble substance displaced the water shown. it's mass is indicated on the triple beam balance. mass = a. 694 b. 693.5 c. 693.0 d.693.8

Which elements are found in glucose, the product of photosynthesis? a. carbon, hydrogen, and oxygen b. carbon and hydrogen c. carbon, nitrogen, and oxygen d. hydrogen, nitrogen, and carbon