What is a known standard and how is it important to document examination?

Exemplars, also called standards, are legally admissible authentic samples of handwriting used for comparison with questioned writing.

Explanation:

They are used by the document examiner to enable her to form an opinion concerning the authenticity of handwriting in dispute. There are two kinds of exemplars (informal which are documents previously executed and known to be genuine) and formal (which are request writing samples). Exemplars are also called known handwriting samples.

the element that provides strength to the exoskeletons of clams and oysters is phosphorus.

this is so because calcium carbonate is the main component in the shells. calcium carbonate is strengthened by phosphorus.

explanation:

✿   this landform has a high elevation and a high relief

✿   this landform is a mountain