19. The layers of the skin are epidermis only

dermis only

hypodermis

epidermis and dermis

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

and after water is usually warmed by the sun the water temperature raises and then evaporates .

yes

no

blue is scattered more than other colors because it travels as shorter, smaller waves. this is why we see a blue sky most of the time.