In the environment, arsenic is found in inorganic and organic forms and in different valence or oxidation states based on geology, ph, redox status and microbial processes.
true / false.

True

Explanation:

Arsenic is an element that has similar behavior to metal, it is toxic to humans. It can be produced by some human activities but it is also available in nature in its organic or inorganic form, this last one being more toxic.

Organic arsenic can be found especially in sea-living organisms.

Inorganic arsenic can be found in the earth's crust and it can affect the acidity levels (PH) of the soil.

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.

16

explanation:

the marks go by 4s