Q1: the metal lid on a jar is screwed on tight. use what you know about the behavior of particles to explain whether it would be a good idea to run some cold or hot water under the lid to to remove it.

q2: engineers recommend the use of structural steel columns and reinforced concrete slabs to build garages. the steel increase the strength of the concrete. these two materials are often used together because they have similar rates of thermal expansion. use your knowledge of the kinetic molecular theory and thermal expansion to explain the importance of steel and concrete having almost the same expansion rates.

just answer one if you don’t know the other one.