dumb
because it takes a while for the skin to change color
Skin Cancer Will Itch if exposed to Sun Light
ozone is the layer of the atmosphere where the ultraviolet rays of the sun are blocked because ultra violet rays of the sun when the skin too much exposed to it cause skin cancer.See also "How does ozone affect human health?" in the "Related questions" section below.
Greater amounts of the skin pigmentation, carotene are produced when the skin is exposed to the sun. Carotene is obtained from a persons diet, for example, carrots are a good source of carotene.
The most common areas of the skin that people apply sunscreen to are the face, neck, arms, legs, and any other exposed skin that is likely to be exposed to the sun.
Melanin
Melanin is the pigment produced in greater amounts when the skin is exposed to the sun. Melanin is produced by cells called melanocytes in response to UV radiation as a defense mechanism to protect the skin from damage.
You can get them anywhere, but usually on skin exposed to sun. Hands, face etc.
UVA and UVB rays cause the sun to burn your skin. When the skin is exposed to the sun for a period of time and without any sunscreen on, the ultraviolet light penetrates the skin, burning it.
Sun exposure can help people with the skin condition eczema.
Ummm most of the time that is from genetics.... It could also be from over sun exposer.
From being in the Sun and having fair skin.