Ducks have waterproof feathers that maintain their body temperature. which body system are these characteristics a part of?
a.
reproductive
b.
respiratory
c.
immune
d.
endocrine
e.
integumentary

E. integumentary

Explanation:

The integumentary system is consisted of hair, feathers, skin, glands, nerves, nails, with its main function being to act as a protective barrier of the body from the outside world. It helps in regulation of the body temperature, retaining body fluids, elimination of waste products, and protection form diseases. The waterproof feathers of the ducks are a nice example of this. They manage to keep their bodies warm in the water, thus helps them a lot in the regulation of the body temperature by being a barrier between the body and the water.

what's the question ?

idk what the options are but

these is a strong electrostatic attraction between the ions hence a lot of energy is needed to overcome this attraction

this is why the boiling points are so high