Violet light (410 nm) and red light (685 nm) pass through a diffraction grating with d=3.33x10^-6. What is the angular separation between them for m=2

Which statement is the best definition of an atom? a) anything that has mass and occupies space. b) the smallest particle that has the properties of an element. c) a substance that cannot be broken down chemically into simpler substances. eliminate d) the smallest unit of a substance that exhibits all of the properties characteristic of that substance.