When water molecules form into ice, . a. hydrogen bonds between water molecules readily break b. the water molecules pack less densely c. evaporation of water molecules happens more readily d. their structure becomes less rigid e. the water molecules jiggle more

B

Explanation:

Since ice is less dense than water, it would make sense for the molecules to pack less densely.

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a