Questions

The Ozone layer which is present in the Earth's atmosphere protects it by restricting from UV or Ultraviolet radiation, the dangerous rays contained by Sun.

The dermis is a layer of the skin of the integumentary system. The dermis lies deep to the superficial epidermis which is also the most superficial layer of the skin. The dermis lies superficial to the underlying hypodermis which is also referred to as subcutaneous tissue.

Among the components of the dermis are: sweat glands, hair follicles, collagen fibers, sensory- nerve endings and arrestor pill muscles.

When water freezes its density decreases.

Water at ordinary temperatures contracts and increases in density as it is cooled, like most substances. But at about 4°C it reaches a maximum density and then decreases in density as it approaches the freezing point.