Atom A and Atom B have the same number of protons and neutrons, but they do not have the same number of electrons. Which statement describes the atoms?

The atoms have the same chemical symbol.
The atoms have the same charge.
The atoms have different atomic numbers.
The atoms have different atomic masses.

Margaret wants to make an orange flavored drink by stirring powdered drink mix into a glass of water. she doesn't like drinks that have small clumps of powdered solid in them, so she wants the drink to be a perfect solution. what factors should margaret not consider when deciding how much powder to add to her glass of water?

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

Which fact represents evidence for the big bang theory?