Which of the following do the objects in the four categories of small objects in the solar system all have in common? a. they all orbit the sun. b. they can all be found in the oort cloud. c. they all contain a nucleus. d. they all are made of gas and ice.

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.