What would be an example of chemical change that took a long time to occur

What do radio waves and microwaves have in common? both are at the side of the spectrum that has the shortest wavelengths. both are at the side of the spectrum that has the lowest radiant energy. both are at the side of the spectrum that has the lowest frequency. both are found next to visible light on the electromagnetic spectrum.

Truck traveling west on the highway experiences an acceleration to the east. what could be the cause of this acceleration

Critical mass is the of material required to produce a chain reaction. a.) minimum amount b.) atomic mass c.) precise amount d.) maximum amount