Which describes the molecular behavior of a solid? i think it's a, but im not sure

a. molecules vibrate around a fixed point.
b. molecules are too far apart to affect each other.
c. molecules have the greatest energy of motion.
d. molecules are rigid and do not move.

In which situation can a mixture always be called a solution

Particles vibrate in a rigid structure and do not move relative to their neighbors.

Which statement best summarizes the importance of ernest rutherford’s gold foil experiment? it proved that all of john dalton’s postulates were true. it verified j. j. thomson’s work on the atomic structure. it showed that an electron circles a nucleus in a fixed-energy orbit. it showed that a nucleus occupies a small part of the whole atom.