The atoms in a sidewalk on a hot summer day are vibrating the atoms in the sidewalk on a freezing day in winter. a. more rapidly than b. more slowly than c. at the same speed as

(A) more rapidly than

Explanation:

With higher temperatures, object's molecules (and atoms) have higher kinetic energy which is due to faster "jiggling" (vibrations). On a hot day these vibrations in the material the sidewalk is made of are more rapid than on a cold day, just as their temperatures differ.

reserve is the answer